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A Designers' Manual 

This book is about designing sustainable human 
settlements, and preserving and extending natural 
systems. It covers aspects of designing and 
maintaining a cultivated ecology in any climate: 
the principles of design; design methods; 
understanding patterns in nature; climatic factors; 
water; soils; earthworks; techniques and strategies 
in the different climatic types; aquaculture; and 
the social, legal, and economic design of human 

It calls into question not only the current 
methods of agriculture but also the very need for a 
formal food agriculture if wastelands and the 
excessive lawn culture within towns and cities are 
devoted to food production and small livestock 
suited to local needs. 

The world can no longer sustain the damage 
caused by modern agriculture, monocultural 
forestry, and thoughtless settlement design, and in 
the near future we will see the end of wasted 
energy, or the end of civilization as we know it, 
due to human-caused pollution and climate 

Strategies for the necessary changes in social 
investment policy, politics itself, and towards 
regional or village self-reliance are now 
desperately needed, and examples of these 
strategies are given. It is hoped that this manual 
will open the global debate that must never end, 
and so give a guide to the form of a future in 
which our children have at least a chance of a 
reasonable existence. 

Bom in 1928 in the small fishing village of Stanley, 
Tasmania, Bill Mollison left school at the age of 15 
to help run the family bakery. He soon went to sea 
as a shark fisherman and seaman bringing vessels 
from post-war disposals to southern ports, and 
until 1954 filled a variety of jobs as a forester, mill- 
worker, trapper, snarer, tractor-driver, and 

Bill joined the CSIRO (Wildlife Survey Section) 
in 1954 and for the next nine years worked in 
many remote locations in Australia as a biologist, 
doing field work on rabbits, locusts, muttonbirds, 
and forest regeneration problems with marsupials. 
In 1963 he spent a year at the Tasmania Museum in 
curatorial duties, then returned to field work with 
the Inland Fisheries Commission surveying the 
macrofauna of inland waters and estuaries, 
recording food chains and water conditions in all 
the rivers and lagoons of Tasmania. 

Returning to studies in 1966, he lived on his wits 
running cattle, bouncing at dances, shark fishing, 
and teaching part-time at an exclusive girls’ 
school. Upon receiving his degree in bio¬ 
geography, he was appointed to the University of 
Tasmania where he later developed the unit of 
Environmental Psychology. During his university 
period (which lasted for 10 years). Bill 

independently researched and published a three- 
volume treatise on the history and genealogies of 
the descendants of the Tasmanian aborigines. In 
1974, he and David Holmgren developed and 
refined the permaculture concept, leading to the 
publication of Permaculture One and Permaculture 

Since leaving the Unversity in 1978, Bill has 
devoted all his energies to furthering the system of 
permaculture and spreading the idea and 
principles worldwide. He has taught thousands of 
students, and has contributed many articles, 
curricula, reports, and recommendations for farm 
projects, urban clusters, and local government 
bodies. In 1981, Bill Mollison received the Right 
Livelihood Award (sometimes called the 
"Alternative Nobel Prize”) for his work in 
environmental design. In recent years, he has 
established a "Trust in Aid" fund to enable 
permaculture teachers to reach groups in need, 
particularly in the poorer parts of the world, with 
the aim of leaving a core of teachers locally to 
continue appropriate educational work. 

Bill Mollison is the Executive Director of the 
Permaculture Institute, which was established in 
1979 to teach the practical design of sustainable 
soil, water, plant, and legal and economic systems 
to students worldwide. 

A Designers' Manual 

by Bill Mollison 

illustrated by Andrew Jeeves 

manuscript and editing, 
Reny Mia Slay 



Publishers for the Permaculture Institute since 1979 

PERMACULTURE: A Designers’ Manual 
Second edition 

156,000 in print as of September, 2002 

O Bill Mollison 1988 

The contents of this book and the word PERMACULTURE O are copyright. Apart from any fair 
dealing for the purpose of private study, research, criticism, or review permitted under the Copyright 
Act, no part of this book may be reproduced by any process without written permission from the 


Publishers for the Permaculture Institute since 1979 

31 Rulla Road 

Sisters Creek, Tasmania, 7325 Australia 

International phone: 61 3 6445 0945 
International fax: 61 3 6445 0944 

Manuscript and photographs Bill Mollison 
Design, illustration, cover and layout Andrew 
Jeeves (Additional illustrations by Jorg Schulze ) 

Typscript, editing, text arrangement Reny Mia Slay 

National Library of Australia 

Mollison, Bill 

Permaculture designers’ manual 
Includes index 
ISBN 0 908228 01 5 

I Organic farming 2 Organic gardening 
I. Jeeves, Andrew, 1956 - 

II Slay, Reny Mia. 1953 - . Ill Title 


Printed in Australia by: McPherson’s Printing Group, Maryborough. Victoria 3465 


Preface, ix •Authors note, ix • Permaculture defined and its use, ix • 
Conventions used, x • Access to information, x • 

Cover story, xi 


1.1 The philosophy behind permaculture, 1 • 1.2 Ethics, 2 • 

1 3 Permaculture in landscape and society, 6 • 1.4 References, 9. 

2.1 Introduction. 10 • 2.2 Science and the thousand names of God, 11 • 
2.3 Applying laws and principles to design, 12 • 2.4 Resources, 16 • 

2.5 Yields, 18 • 2.6 Cycles: a niche in time. 23 • 2.7 Pyramids, food 
webs, growth and vegetarianism, 28 • 2.8 Complexity and 
connections. 30 • 2.9 Order or chaos, 31 • 2.10 Permitted and forced 
functions, 31 • 2.11 Diversity, 32 • 2.12 Stability, 33 • 2.13 Time and 
yield, 33 *2.14 Principle summary, 34 • 2.15 References. 35. 


3.1 Introduction, 36 • 3.2 Analysis: Design by listing characteristics of 
components, 37 • 3 3 Observation: Design by expanding on direct 
observations of a site. 43 • 3.4 Deduction from nature: Design by 
adopting lessons learnt from nature, 44 • 3.5 Options and decisions: 
Design as a selection of options or pathways based on decisions, 47 • 

3.6 Data overlay: Design by map overlays, 47 • 3.7 Random 
assembly: Design by assessing the results of random assemblies, 47 • 
3.8 Flow diagrams: Design for work places. 48 • 3.9 Zone and sector 
analysis: Design by the application of a master pattern, 49 • 

3.10 Zoning of information and ethics, 57 • 3.11 Incremental design, 58 
3.12 Summary of design methods, 58 • 3.13 The concepts of guilds in 
nature, 59 • 3.14 Succession: evolution of a system. 64 • 3.15 The 
establishment and maintenance of systems, 65 • 3.16 General practical 
procedures in property design, 68 • 3.17 Principle summary, 69. 



4.1 Introduction, 70 • 4.2 A general pattern model of events, 71 • 

4.3 Matrices and the strategies of compacting and complexing 
components, 72 • 4.4 Properties of media, 75 • 4.5 Boundary 
conditions, 76 • 4.6 The harmonics and geometries of boundaries, 78 • 

4.7 Compatible and incompatible borders and components, 79 • 

4.8 The timing and shaping of events, 81 • 4.9 Spirals, 83 • 4.10 Flow 
over landscape and objects, 83 • 4.11 Open flow and and flow 
patterns, 87 • 4.12 Toroidal phenomena, 88 • 4.13 Dimensions and 
potentials, 88 • 4.14 Closed (sperical) models; accretion and 


expulsion, 88 • 4.15 Branching and its effects; conduits, 89 • 

4.16 Orders of magnitude in branches. 91 • 4.17 Orders and 
dimensions, 92 • 4.18 Classification of events, 93 • 4.19 Time and 
relativity in the model, 93 • 4.20 The world we live in as a 
tessellation of events, 94 • 4.21 Introduction to pattern 
applications, 95 • 4.22 The tribal use of patterning, 96 • 4.23 The 
mnemonics of meaning, 99 • 4.24 Patterns of society, 100 • 4.25 The 
arts in the service of life, 100 • 4.26 Additional pattern 
applications, 101 • 4.27 References and further reading, 102 • 

4.28 Designers’ checklist, 105. 


5.1 Introduction, 106 • 5.2 The classification of broad climatic 
zones, 107 • 53 Patterning in global weather systems; the engines of 
the atmosphere, 107 • 5.4 Precipitation, 110 • 5.5 Radiation, 113 • 

5.6 Wind, 121 • 5.7 Landscape effects, 132 • 5.8 Latitude effects, 134 • 
5.9 References, 134 • 5.10 Designers checklist. 135. 


6.1 Introduction. 138 • 6.2 The biomass of the tree, 138 • 6.3 Wind 
effects, 139 • 6.4 Temperature effects, 142 • 6.5 Trees and 
precipitation, 142 • 6.6 How a tree interacts with rain, 147 • 

6.7 Summary, 150 • 6.8 References, 151 


7.1 Introduction. 152 • 7.2 Regional intervention in the water 
cycle, 153 • 7.3 Earthworks for water conservation and storage, 155 • 

7.4 Reduction of water used in sewage systems. 170 • 7.5 The 
purification of polluted waters, 172 • 7.6 Natural swimming pools, 180 • 

7.7 Designers' Checklist. 181 • 7.8 References, 181. 


8.1 Introduction. 182 • 8.2 Soil and health, 184 • 8.3 Tribal and 
traditional soil classifications, 185 • 8.4 The structure of soils, 186 • 

8.5 Soil and water elements, 187 • 8.6 Primary nutrients for plants, 187 • 

8.7 The distribution of elements in the soil profile, 188 • 8.8 pH and 
soils, 195 • 8.9 Soil composition, 199 • 8.10 Soil pores and crumb 
structure, 201 • 8.11 Gaseous content and processes in soils, 204 • 

8.12 The soil biota, 205 • 8.13 Difficult soils, 208 • 8.14 Plant 
analysis for mineral deficiencies; some remedies, 209 • 8.15 Biological 
indicators of soil and soil conditions, 212 • 8.16 Seed pelleting, 214 • 
8.17 Soil erosion, 214 • 8.18 Soil rehabilitation, 215 • 8.19 Soils in 
house foundations, 221 • 8.20 Life in earth, 222 • 8.21 The respiration 
of earth, 224 • 8.22 Designers' checklist, 225 • 8.23 References, 226. 



9.1 Introduction. 227 • 9.2 Planning earthworks. 228 • 9.3 Planting 
after earthworks. 229 • 9.4 Slope measure, 230 • 9.5 Levels and 
levelling. 232 • 9.6 Types of earthworks, 234 • 9.7 Earth constructs, 237 
9.8 Moving the earth, 241 • 9.9 Earth resources, 247 • 

9.10 References, 249. 


10.1 Introduction, 250 • 10.2 Climatic types, 251 • 10.3 Tropical 
soils. 253 • 10.4 Earthshaping in the tropics, 259 • 10.5 House 
design, 261 • 10.6 The tropical home garden, 266 • 10.7 Integrated 
land management. 277 • 10.8 Elements of a village complex in the 
humid tropics, 279 • 10.9 Evolving a polyculture, 279 • 10.10 Themes 
on a coconut- or palm-dominant polyculture, 283 • 

10.11 Pioneering, 293 • 10.12 Animal tractor" systems, 299 • 

10.13 Grassland and range management, 300 • 10.14 Humid tropical 
coast stabilisation and shelterbelts, 303 • 10.15 Low island and coral 
cay strategies, 30» • 10.16 Designers checklist, 307 • 

10.17 References. 307. 


11.1 Introduction, 308 • 11.2 Precipitation. 310 • 

11.3 Temperature, 312 • 11.4 Soils, 312 • 11.5 landscape features in 
deserts. 316 • 11.6 Harvesting of water in arid lands, 336 • 11.7 The 
desert house. 359 • 11.8 The desert garden, 371 • 11.9 Garden 
irrigation systems, 381 • 11.10 Desert settlement—broad 
strategies, 11.11 Plant themes for drylands, 390 • 11.12 Animal 
systems in drylands. 397 • 11.13 Desertification and the salting 
of soils. 401 • 11.14 Cold and montane deserts, 409 • 11.15 Designers' 
checklist. 410 • 11.16 References. 410. 


12.1 Introduction. 411 • 12.2 Characteristics of a humid cool climate, 412 

12.3 Soils. 413 • 12.4 Landform and water conservation, 413 • 

12.5 Settlement and house design, 414 • 12.6 The home garden, 417 • 
12.7 Berry fruits, 420 • 12.8 Glasshouse growing, 422 • 

12.9 Orchards. 423 • 12.10 Farm forestry, 425 • 12.11 Free-range forage 
systems, 427 • 12.12 The lawn, 434 • 12.13 Grasslands, 435 • 

12.14 Rangelands. 442 • 12.15 Cold climates, 446 • 12.16 Wildfire, 451 • 
12.17 Designers' checklist, 456 • 12.18 References, 457. >7. 


13.1 Introduction, 458 • 13.2 The case for aquaculture, 459 • 

133 Some factors affecting total useful yields, 461 • 13.4 Choice of fish 
species (varieties, food, health) and factors in yield, 470 • 

13.5 Fish pond configurations and food supply, 472 • 13.6 Farming 
invertebrates for fish food, 491 • 13.7 Channel, canal, chinampa, 495 • 
13.8 Yields outside the pond • 13.9 Bringing in the harvest, 499 • 

13.10 Traditional and new water polycultures, 500 • 


13.11 Designers' checklist, 502 • 13.12 References, 


14.1 Introduction, 506 • 14.2 Ethical basis of an alternative nation, 507 
14 3 A new United Nations, 508 • 14.4 Alternatives to political 
systems, 509 • 14.5 Bioregional organisation, 510 • 14.6 Extended 
families, 514 • 14.7 Trusts and legal strategies, 515 • 

14.8 Developmental and property trusts, 518 • 14.9 Village 
development, 519 • 14.10 Effective working groups and right 
livelihood, 530 • 14.11 Money and finance, 533 • 14.12 Land 
access, 545 • 14.13 An ethical investment movement, 551 • 

14.14 Effective aid, 555 • 14.15 Futures, 557 • 14.16 References and 
resources, 558, 

Plant list by common name, 561. 

Plant list by species name, 563. 

Glossary, 566. 

Resources, 567. 

References. 568. 

Index, 569. 


To many of us who experienced the ferment of the late 
1960’s, there seemed to be no positive direction 
forward, although almost everybody could define those 
aspects of the global society that they rejected, and 
these include military adventurism, the bomb, ruthless 
land exploitation, the arrogance of polluters, and a 
general insensitivity to human and environmental 

From 1972-1974, 1 spent some time (latterly with 
David Holmgren) in developing an interdisciplinary 
earth science (permaculture) with a potential for 
positivistic, integrated, and global outreach. It was 
January 1981 before the concept of permaculture 
seemed to have matured sufficiently to be taught as an 
applied design system, when the first 26 students 
graduated from an intensive 140-hour lecture series. 
Today, we can count thousands of people who have 
attended permaculture design courses, workshops, 
lectures, and seminars. Graduates now form a loose 
global network, and are effectively acting in many 
countries. The permaculture movement has no central 
structure, but rather a strong sense of shared work. 
Everybody is free to act as an individual, to form a 
small group, or to work within any other organisation. 
We cooperate with many other groups with diverse 
beliefs and practices; our system includes good 
practices from many disciplines and systems, and offers 
them as an integrated whole. 

Great changes are taking place. These are not as a 
result of any one group or teaching, but as a result of 
millions of people defining one or more ways in which 
they can conserve energy, aid local self-reliance, or 
provide for themselves. All of us would acknowledge 
our own work as modest; it is the totality of such 
modest work that is impressive. There is so much to do, 
and there will never be enough people to do it. We 
must all try to increase our skills, to model trials, and to 
pass on the results. If a job is not being done, we can 
form a small group and do it (when we criticise others, 
we usually point the finger at ourselves!) It doesn’t 
matter if the work we do carries the "permaculture" 
label, just that we do it. 

By 1984, it had become clear that many of the systems 
we had proposed a decade earlier did, in fact, 
constitute a sustainable earth care system. Almost all 
that we had proposed was tested and tried, and where 
the skills and capital existed, people could make a 
living from products derived from stable landscapes, 
although this is not a primary aim of permaculture. 
which seeks first to stabilise and care for land, then to 
serve household regional and local needs, and only 
thereafter to produce a surplus for sale or exchange. 

In 1984, we held our first international permaculture 
conference, and awarded about 50 applied diplomas to 
those who had served two years of applied work since 
their design course. Those of us who belong to the 

permaculture family have cause to be proud, but not 
complacent. Work has scarcely begun, but we have a 
great team of people which increases in numbers daily. 
To empower the powerless and create "a million 
villages" to replace nation-states is the only safe future 
for the preservation of the biosphere. Let 
interdependence and personal responsibility be our 


This volume was written for teachers, students, and 
designers; it follows on and greatly englarges on the 
initial introductory texts Permaculture One (1978) and 
Permaculture Tuw (1979), both of which are still in 
demand a decade after publication. Very little of the 
material in this book is reproduced from the found¬ 
ation texts. 

Each volume of this work carries a surcharge of 50c 
which will be paid by Tagari Publications to the 
Permaculture Institute. The Institute (a public trust) 
holds the funds so generated in trust for tree-planting, 
and from time to time releases monies to selected 
groups who are active in permanent reafforestation. In 
this way, both publisher and readers can have a clear 
conscience about the use of the paper in this volume, or 
in any book published by Tagari I’ublications. Our trust 
funds are open to receive any such levy from other 
ethical publishers 


Permaculture is a word coined by the author. Its 
copyright is vested in the Permaculture Institutes and 
their College of Graduates, and is guarded by them for 
the purposes of consistent education. 

Permaculture (permanent agriculture) is the con¬ 
scious design and maintenance of agriculturally 
productive ecosystems which have the diversity, 
stability, and resilience of natural ecosystems. It is the 
harmonious integration of landscape and people 
providing their food, energy, shelter, and other material 
and non-material needs in a sustainable way. Without 
permanent agriculture there is no possibility of a stable 
social order. 

Permaculture design is a system of assembling 
conceptual, material, and strategic components in a 
pattern which functions to benefit life in all its forms. 

The philosophy behind permaculture is one of work¬ 
ing with, rather than against, nature; of protracted and 
thoughtful observation rather than protracted and 
thoughtless action; of looking at systems in all their 
functions, rather than asking only one yield of them; 
and of allowing systems to demonstrate their own 



The word "permaculture" can be used by anybody 
adhering to the ethics and principles expressed herein. 
The only restriction on use is that of teaching; only 
graduates of a Permaculture Institute can teach 
"permaculture", and they adhere to agreed-on 
cumculae developed by the College of Graduates of the 
Institutes of Permaculture. 


References and Abbreviations : Minor references are 
given in the text, and those useful to chapter contents 
only are located at the close of those chapters. Key 
references are assembled at the close of the book, and 
are superscripted as numbers in the text. 


Material in this work can be fairly easily accessed in 
these ways: chapter and section contents are listed in 
the Table of Contents. Main subjects are listed in the 
Index. There is a list of the common and Latin names of 
plants used in the text located in the Appendix. Also 
located in the Appendix is a glossary of terms used; 
some few words are recently coined or (like "permacul¬ 
ture") are the conceit of the author. 

To forestall needless correspondence, subscription to 
the International Permaculture Journal (113 Enmore Rd, 
Enmore, NSW 2042, Australia) gives information on 
permaculture themes, reviews recent publications, 
gives news of events, publishes a directory of 
permaculture centres, and has a host of other useful 
data. Further resources are also listed in the Appendix. 

Seasons and Baflfcag So that the text and figures 
are useful and readable in both hemispheres, I have 
used the words "sun-side" or "sunwards", and "shade- 
side" or "polewards" rather than south and north, and 
converted months to seasons as below: 














































These may be further refined by the use of "first 
week of..For the same reason, the symbol below is 
used in figures to indicate the sun direction rather than 
the north or south symbol: 


One hopes this prevents the problem of all those 
good North Americans wandering on the north face of 
their hills, looking for the sun, poised dangerously 
upside-down on the Earth as they are. 



The great oval of the design represents the egg of life; 
that quantity of life which cannot be created or des¬ 
troyed, but from within which all things that live are 
expressed. Within the egg is coiled the rainbow snake, 
the Earth-shaper of Australian and American 
aboriginal peoples. 

"We have a legend that explains the forma 
tlon of the hills, the rivers, and all the shapes 
of the land, Everytlme it rains and I see a 
beautiful rainbow 1 am reminded of the legend 
of the the Rainbow Serpent... 

In the beginning the earth was flat, a vast 
grey plain. As the Rainbow Serpent wound his 
way across the land, the movement of his body 
heaped up the mountains and dug troughs for 
the rivers. With each thrust of his huge multi¬ 
coloured body a new land form was created. 

At last, tired with the effort of shaping the 
earth, he crawled Into a waterhole. The cool 
water washed over his vast body, cooling and 
soothing him... Each time the animals visited 
the waterhole. they were careful not to disturb 
the Rainbow Serpent, for although they could 

not see him they knew he was there. Then one 
day. after a huge rainstorm, they saw him. His 
huge coloured body was arching from the 
waterhole. over the tree tops, up through the 
clouds, across the plain to another waterhole. 

To this day the Aborigines are careful not to 
disturb the Rainbow Serpent, as they see him. 
going across the sky from one waterhole to 
another. - 

(From pf thf Preamtims/ 

compiled by Hugh Rule and Stuart Goodman, 
published by William Collins, Sydney, 1979.) 

Within the body of the Rainbow Serpent is contained 
the tree of life, which itself expresses the general pattern 
of life forms, as further elaborated in the chapter on 
pattern in this book. Its roots are in earth, and its crown 
in rain, sunlight and wind. Elemental forces and flows 
shown external to the oval represent the physical 
environment, the sun, and the matter of the universe; 
the materials from which life on earth is formed. The 
whole cycle and form is dedicated, as is this book, to 
the complexity of life on Earth. 




Although this book is about design, it is also about 
values and ethics, and above all about a sense of 
peronal responsibility for earth care. I have written at 
times in the first person, to indicate that it is not a 
detached, impersonal, or even unbiased document. 
Every book or publication has an author, and what that 
author chooses to write about is subjective, for that 
person alone determines the subject, content, and the 
values expressed or omitted. I am not detached from, 
but have been passionately involved with this earth, 
and so herein give a brief vision of what I think can be 
achieved by anyone. 

The sad reality is that we are in danger of perishing 
from our own stupidity and lack of personal 
responsibility to life. If we become extinct because of 
factors beyond our control, then we can at least die 
with pride in ourselves, but to create a mess in which 
we perish by our own inaction makes nonsense of our 
claims to consciousness and morality. 

There is too much contemporary evidence of 
ecological disaster which appals me. and it should 
frighten you, too. Our consumptive lifestyle has led us 
to the very brink of annihilation. We have expanded 
our right to live on the earth to an entitlement to 
conquer the earth, yet "conquerors" of nature always 
lose. To accumulate wealth, power, or land beyond 
one’s needs in a limited world is to be truly immoral, 
be it as an individual, an institution, or a nation-state 

What we have done, we can undo. There is no longer 
time to waste nor any need to accumulate more 
evidence of disasters; the time for action is here. I 
deeply believe that people are the only critical resource 
needed by people. We ourselves, if we organise our 
talents, are sufficient to each other. What is more, we 
will either survive together, or none of us will survive. 
To fight between ourselves is as stupid and wasteful as 

•ter 1 

it is to fight during times of natural disasters, when 
everyone’s cooperation is vital. 

A person of courage today is a person of peace. The 
courage we need is to refuse authority and to accept 
only personally responsible decisions. Like war, 
growth at any cost is an outmoded and discredited 
concept. It is our lives which are being laid to waste. 
What is worse, it is our children s world which is being 
destroyed. It is therefore our only possible decision to 
withhold all support for destructive systems, and to 
cease to invest our lives in our own annihilation. 

The only ethical decision is to take responsibility for our 
own existence and that of our children. 

link* It now 

Most thinking people would agree that we have 
arrived at final and irrevocable decisions that will 
abolish or sustain life on this earth. We can cither 
ignore the madness of uncontrolled industrial growth 
and defence spending that is in small bites, or large 
catastrophes, eroding life forms every day, or take the 
path to life and survival. 

Information and humanity, science and 
understanding, are in transition. Long ago, we began 
by wondering mainly about what is most distant; 
astronomy and astrology were our ancient pre¬ 
occupations. We progressed, millenia by millenia, to 
enumerating the wonders of earth. First by naming 
things, then by categorising them, and more recently 
by deciding how they function and what work they do 
within and without themselves. This analysis has 
resulted in the development of different sciences, 
disciplines and technologies; a welter of names and the 
sundering of parts; a proliferation of specialists; and a 
consequent inability to foresee results or to design 
integrated systems. 

The present great shift in emphasis is on how the 
parts interact, how they work together with each other. 


issccance or harmony in life systems or society 
a achieved Life *5 cooperative rather than competitive, 
and life forms of very different qualities may interact 
beneficially with one another and with their physical 
environment. Even "the bacteria... live by 
collaboration, accommodation, exchange, and barter" 
(Lewis Thomas, 1974). 

Eiincicle ot Cooperation. 

Cooperation, not competition, is the very basis of 
existing life systems and of future survival. 

There are many opportunities to create systems that 
work from the elements and technologies that exist. 
Perhaps we should do nothing else for the next century 
but apply our knowledge We already know how to 
build, maintain, and inhabit sustainable systems. Every 
essential problem is solved, but in the everyday life of 
people this is hardly apparent. The wage-slave, 
peasant, landlord, and industrialist alike are deprived 
of the leisure and the life spirit that is possible in a 
cooperative society which applies its knowledge Both 
warders and prisoners are equally captive in the 
society in which we live. 

If we question why we are here and what life is. then 
we lead ourselves into both science and mysticism 
which are coming closer together as science itself 
approaches its conceptual limits. As for life, it is the 
most open of open systems, able to take from the 
energy resources in time and to re-express itself not 
only as a lifetime but as a descent and an evolution. 

Lovelock (1979) has perhaps best expressed a 
philosophy, or insight, which links science and tribal 
beliefs: he sees the earth, and the universe, as a thought 
process, or as a self-regulating, self-constructed and 
reactive system, creating and preserving the conditions 
that make life possible, and actively adjusting to 
regulate disturbances. Humanity however, in its 
present mindlessness, may be the one disturbance that 
the earth cannot tolerate. 

The Gala hypothesis Is for those who like to 
walk or simply stand and stare, to wonder 
about the earth and the Ufe It bears, and to 
speculate about the consequences of our own 
presence here. It Is an alternative to that 
pessimistic view which sees nature as a 
primitive force to be subdued and conquered. 

It Is also an alternative to that equally 
depressing picture of our planet as a 
demented spaceship, forever travelling, 
driverless and purposeless, around an Inner 
circle of the sun. 

(J.E. Lovelock, 1979). 

For every scientific statement articulated on energy, the 
Aboriginal tribespeople of Australia have an 
equivalent statement on life. Life, they say, is a totality 
neither created nor destroyed. It can be imagined as an 
egg from which all tribes (life forms) issue and to 

which all return. The ideal way in which to spend one's 
time is in the perfection of the expression of life, to lead 
the most evolved life possible, and to assist in and 
celebrate the existence of life forms other than humans, 
for all come from the same egg. 

The totality of this outlook leads to a meaningful 
daily existence, in which one sees each quantum of life 
eternally trying to perfect an expression towards a 
future, and possibly transcendental, perfection. It is all 
the more horrific, therefore, that tribal peoples, whose 
aim was to develop a conceptual and spiritual 
existence, have encountered a crude scientific and 
material culture whose life aim is not only unstated, 
but which relies on pseudo-economic and techno¬ 
logical systems for its existence. 

The experience of the natural world and its laws has 
almost been abandoned for closed, artificial, and 
meaningless lives, perhaps best typified by the dreams 
of those who would live in space satellites and 
abandon a dying earth. 

I believe that unless we adopt sophisticated 
aboriginal belief systems and learn respect for all life, 
then we lose our own. not only as lifetime but also as 
any future opportunity to evolve our potential. 
Whether we continue, without an ethic or a philo¬ 
sophy. like abandoned and orphaned children, or 
whether we create opportunities to achieve maturity, 
balance, and harmony is the only real question that 
faces the present generation. This is the debate that 
must never stop. 

A young woman once came to me after a lecture in 
which I wondered at the various concepts of afterlife; 
the plethora of heavens" offered by various groups. 
Her view was.This is heaven, right here. This is it. 
Give it all you've got ." 

I couldn’t better that advice. The heaven, or hell, we 
live in is of our own making. An afterlife, if such exists, 
can be no different for each of us. 

_ 1 ^_ 


In earlier days, several of us researched community 
ethics, as adopted by older religious and cooperative 
groups, seeking for universal principles to guide our 
own actions. Although many of these guidelines 
contained as many as 18 principles, most of these can 
be included in the three below (and even the second 
and third arise from the first): 

1. CARE OF THE EARTH: Provision for all life systems 
to continue and multiply. 

2. CARE OF PEOPLE: Provision for people to access 
those resources necessary to their existence. 

CONSUMPTION: By governing our own needs, we can 
set resources aside to further the above principles. 


This ethic is a very simple statement of guidance, and 
serves well to illuminate everyday endeavours. It can 
be coupled to a determination to make our own way: 
to be neither employers nor employees, landlords nor 
tenants, but to be self-reliant as individuals and to 
cooperate as groups. 

For the sake of the earth itself, I evolved a 
philosophy close to Taoism from my experiences with 
natural systems. As it was stated in Permaculture Two. it 
is a philosophy of working with rather than against 
nature; of protracted and thoughtful observation 
rather than protracted and thoughtless action; of 
looking at systems and people in all their functions, 
rather than asking only one yield of them; and of 
allowing systems to demonstrate their own evolutions. 
A basic question that can be asked in two ways is: 

"What can I get from this land, or person?" or 

"What does this person, or land, have to give if 1 
cooperate with them?" 

Of these two approaches, the former leads to war 
and waste, the latter to peace and plenty 

Most conflicts, I find, lay in how such questions are 
asked, and not in the answers to any question. Or. to 
put it another way, we are dearly looking for the right 
questions rather than for answers. We should be alert 
to rephrase or refuse the "wrong" question 

It has become evident that unity in people comes 
from a common adherence to a set of ethical prindples, 
each of us perhaps going our own way. at our own 
pace, and within the limits of our resources, yet all 
leading to the same goals, which in our own case is 
that of a living, complex, and sustainable earth. Those 
who agree on such ethics, philosophies, and goals form 
a global nation. 

How do a people evolve an ethic, and why should 
we bother to do so? 

Humans are thinking beings, with long memories, 
oral and written records, and the ability to investigate 
the distant past by applying a variety of techniques 
from dendrochronology to archaeology, pollen analy¬ 
sis to the geological sciences. It is therefore evident that 
behaviours in the natural world which we thought 
appropriate at one time later prove to be damaging to 
our own society in the long-term (e.g. the effects of 
biocidal pest controls on soils and water) 

Thus, we are led by information, reflection, and 
careful investigation to moderate, abandon, or forbid 
certain behaviours and substances that in the long¬ 
term threaten our own survival; u* acl to survive 
Conservative and cautious rules of behaviour are 
evolved. This is a rational and sensible process, 
responsible for many taboos in tribal societies. 

From a great many case histories we can list some 
rules of use, for example the RULE OF NECESSITOUS 
USE—that we leave any natural system alone until we 
are, of strict necessity, forced to use it. We may then 

USE—having found it necessary to use a natural 
resource, we may insist on every attempt to: 

• Reduce waste, hence pollution; 

• Thoroughly replace lost minerals; 

• Do a careful energy accounting; and 

• Make an assessment of the long-term, negative, 
biosocial effects on society, and act to buffer or 
eliminate these. 

In practice, we evolve over time to various forms of 
accounting for our actions. Such accounts are fiscal, 
social, environmental, aesthetic, or energetic in nature, 
and all are appropriate to our own survival. 

Consideration of these rules of necessitous and 
conservative use may lead us, step by step, to the basic 
realisation of our interconnectedness with nature; that 
we depend on good health in all systems for our 
survival. Thus, we widen the self-interested idea of 
human survival (on the basis of past famine and 
environmental disaster) to include the idea of "the 
survival of natural systems", and can see. for example, 
that when we lose plant and animal species due to our 
actions, we lose many survival opportunities. Our fates 
are intertwined. This process, or something like it, is 
common to every group of people who evolve a 
general earthcare ethic. 

Having developed an earthcare ethic by assessing 
our best course for survival, we then turn to our 
relationships with others. Here, we observe a general 
rule of nature: that cooperative species and associa¬ 
tions of self-supporting species (like mycorrhi/.a on 
tree roots) make healthy communities. Such lessons 
lead us to a sensible resolve to cooperate and take 
support roles in society, to foster an interdependence 
which values the individual's contributions rather than 
forms of opposition or competition. 

Although initially we can see how helping our 
family and friends assists us in our own survival, we 
may evolve the mature ethic that sees all humankind as 
family, and all life as allied associations. Thus, we 
expand people care to species care, for all life has common 
origins. All are "our family". 

We see how enlightened self-interest leads us to 
evolve ethics of sustainable and sensible behaviour. 
These then, are the ethics expressed in permaculture. 
Having evolved ethics, we can then devise ways to 
apply them to our lives, economies, gardens, land, and 
nature. This is what this book is about: the mechan¬ 
isms of mature ethical behaviour, or how to act to 
sustain the earth. 

There is more than one way to achieve permanence 
and stability in land or society. The peasant approach is 
well described by King (6) for old China. Here people 
hauled nutrients from canals, cesspits, pathways and 
forests to an annual grain culture. We could describe 
this as "feudal permanence" for its methods, period 
and politics. People were bound to the landscape by 
unremitting toil, and in service to a state or landlord. 
This leads eventually to famine and revolution. 

A second approach is on permanent pasture of 
prairie, pampas, and modern western farms, where 
large holdings and few people create vast grazing 
leases, usually for a single species of animal. This is 
best described as "baronial permanence" with 

{Continued on page 6...I 






,'SsJS's. * 


C. PERMACULTURE; 70% cropland devoted to forage farming year 8 

FIGURE 1 1 10 permacultum over a period of 3 8 years (the transition penod). 

™ M C0NTEMP0R¥ agriculture to a era® 

rtnMAUULl UHt. croplands, retrofitting the house for energy conservalion. and 

I have attempted to cost contempory agriculture against a changeover producing some (if not ail) fuel on the farm. 

C. PERMACULTURE; 70% cropland devoted to forage farming YEAR 8 

FIGURE 1.1 (Continued) 


The accounting is in sections as follows 

I Cub (Dollar) Accounting. 

Bit 1. Income from total product on the farm 

{continued next page....} 


•rom page 3) 

near-regal properties of immense extent, working at 
the lowest possible level of land use (pasture or 
cropland is the least productive use of land we can 
devise). Such systems, once mechanised, destroy whole 
landscapes and soil complexes. They can then best be 
typified as agricultural deserts. 

Forests, not seen by industrial man as anything but 
wood, are another permanent agriculture. But they 
need generations of care and knowledge, and hence a 
tribal or communal reverence only found in stable 
communities. This then, is the communal permanence 
many of us seek: to be able to plant a pecan or citrus 
when we are old, and to know it will not be cut down 
by our children s children. 

The further we depart from communal permanence, 
the greater the risk of tyranny, feudalism, and 
revolution and the more work for less yield. Any error 
or disturbance can then bring disaster, as can a drought 
year in a desert grain crop or a distant political 
decision on tariffs. 

The real risk is that the needs of those people 
working "on the ground", the inhabitants, are 
overthrown by the needs (or greeds) of commerce and 
centralised power; that the forest is cut for warships or 
newspaper and we are reduced to serfs in a barren 
landscape. This has been the fate of peasant Europe, 
Ireland, and much of the third world. 

The characteristic that typifies all permanent 
agricultures is that the needs of the system for energy 
are provided by that system. Modem crop agriculture 
is totally dependent on external energies—hence the oil 
problem and its associated pollution. 

Figure 1.1 is a very simple but sufficient illustration 
of the case I am making. Selected forests not only yield 
more than annual crops, but provide a diverse nutrient 
and fuel resource for such crops. 

Without permanent agriculture there is no possibility 
of a stable social order. Thus, the move from pro¬ 
ductive permanent systems (where the land is held 
in common), to annual, commercial agricultures where 
land is regarded as a commodity, involves a departure 


BaL2; Cost ot producing that income in real terms (excess cost over 
income represents subsidies. Note that any farm ’profits* are 
achieved by subsidy: the dollar costs do not balance until organic 
farming is achieved Farm income is achieved by reducing production 

II Energy Accounting. 

Bai_3: Oil (or calories) as machinery, fuels, fertilisers, biocides 
Starts at 10:1 against (loss) in conventional farming, and can reach a 
1:120 gam in conservation farming/permaculture with firewood and 

BaL_4: Energy produced on farm; includes fuel oils from crop, 
firewood, calories in food produced (solar energy is a constant, but it 
contnbutes most energy in conservation farmin&fpermacufture). 

III Environmental Accounting. 

BaL5: Soil loss; includes humus loss and mineral nutrient loss. 

Bati: Efficiency of water use and soil water storage 
BaLZ: Pollution produced (poisoning of atmosphere, soils, water) by 
fuels, biocides, and fertilisers. Soils are created in conservation 
farming/permaculture. water conserved, and pollutants removed. 

from a low- to a high-energy society, the use of land in 
an exploitative way, and a demand for external energy 
resources, mainly provided by the third world. People 
think I am slightly crazy when I tell them to go home 
and garden, or not to involve themselves in broadscale 
mechanised agriculture; but a little thought and 
reading will convince them that this is, in fact, the 
solution to many world problems. 

What is now possible is a totally new synthesis of 
plant and animal systems, using a post-industrial or 
even computerised approach to system design, 
applying the principles of whole-system energy flows 
as devised by Odum (1971), and the principles of 
ecology as enunciated by Watt ,1J) and others. It is, in 
the vernacular, a whole new ball game to devise 
permaculture systems for local, regional, and personal 

Had we taught this approach from the beginning, we 
would all be in a stable and functional landscape, but 
our grandparents failed us, and (perhaps for lack of 
time or information) set up the present, and 
continuing, mis-designed households, towns, and 
cities. The concept of 'free'' energy put the final nail in 
the coffin of commonsense community, and enabled 
materialistic societies to rob distant peoples, oblivious 
of the inevitable accounting to come. 



As the basis of permaculture is beneficial design, it can 
be added to all other ethical training and skills, and has 
the potential of taking a place in all human 
endeavours. In the broad landscape, however, 
permaculture concentrates on already-settled areas 
and agricultural lands. Almost all of these need drastic 
rehabilitation and re-thinking. One certain result of 
using our skills to integrate food supply and 

IV Conservation Accounting; 

Lite Form Richness. 

BiL8: Genetic richness in crops and livestock. 

Bar 9 : Soil life (biomass). 

Bar IQ Forest biomass and wildlife richness. 

Baf.ll: Loss to pests 

V Social Accounting 

BaLl2: Employment on farm (human design and/or skills replace 
most machine systems). 

Bar. 13: Food quality produced 

Bai 14: Human and environmental health. 

Baf . 15; Life quality, as "right livelihood*. 

Thus, it can be seen that a transition from contempory western 
agriculture to conservation farming and permaculture has most 
benefits for people and to other life forms; farming can become 
energy productive, and farms can produce real income without public 
subsidy, in particular it farm products are already matched to local or 
regional demand 


settlement, to catch water from our roof areas, and to 
place nearby a zone of fuel forest which receives 
wastes and supplies energy, will be to free most of the 
area of the globe for the rehabilitation of natural 
systems. These need never be looked upon as "of use to 
people", except in the very broad sense of global 

The real difference between a cultivated (designed) 
ecosystem, and a natural system is that the great 
majority of species (and biomass) in the cultivated 
ecology is intended for the use of humans or their 
livestock. We are only a small part of the total primeval 
or natural species assembly, and only a small part of its 
yields are directly available to us. But in our own 
gardens, almost every plant is selected to provide or 
support some direct yield for people. Household 
design relates principally to the needs of people; it is 
thus human-centred (anthropocentric). 

This is a valid aim for settlement design, but we also 
need a nature-centred ethic for wilderness con¬ 
servation. We cannot, however, do much for nature 
if we do not govern our greed, and if we do not supply 
our needs from our existing settlements. If we can 
achieve this aim, we can withdraw from much of the 
agricultural landscape, and allow natural systems to 

Recycling of nutrients and energy in nature is a 
function of many species. In our gardens, it is our own 
responsibility to return wastes (via compost or mulch) 
to the soil and plants. We actively create soil in our 
gardens, whereas in nature many other species carry 
out that function. Around our homes we can catch 
water for garden use, but we rely on natural forested 
landscapes to provide the condenser leaves and clouds 
to keep rivers running with clean water, to maintain 
the global atmosphere, and to lock up our gaseous 
pollutants. Thus, even anthropocentric people would 
be well-advised to pay close attention to, and to assist 
in, the conservation of existing forests and the 
rehabilitation of degraded lands. Our own survival 
demands that we preserve all existing species, and 
allow them a place to live. 

We have abused the land and laid waste to systems 
we need never have disturbed had we attended to our 
home gardens and settlements. If we need to state a set 
of ethics on natural systems, then let it be thus: 

• Implacable and uncompromising opposition to 
further disturbance of any remaining natural forests, 
where most species are still in balance; 

• Vigorous rehabilitation of degraded and damaged 
natural systems to stable states; 

• Establishment of plant systems for our own use on 
the least amount of land we can use for our existence; 

• Establishment of plant and animal refuges for rare 
or threatened species. 

Permaculture as a design system deals primarily 
with the third statement above, but all people who act 
responsibly in fact subscribe to the first and second 
statements. That said, I believe we should use all the 

species we need or can find to use in our own 
settlement designs, providing they are not locally 
rampant and invasive. 

Whether we approve of it or not, the world about us 
continually changes. Some would want to keep 
everything the same, but history, palaeontology, and 
commonsense tells us that all has changed, is changing, 
will change. In a world where we are losing forests, 
species, and whole ecosystems, there are three 
concurrent and parallel responses to the environment: 

IES, to leave the wilderness to heal itself. 

LAND using complex pioneer species and long-term 
plant assemblies (trees, shrubs, ground covers). 

ENVIRONMENT with as many species as we can save, 
or have need for, from wherever on earth they come. 

We are fast approaching the point where we need 
refuges for all global life forms, as well as regional, 
national, or state parks for indigenous forms of plants 
and animals. While we see our local flora and fauna as 
'native", we may also logically see all life as "native to 
earth". While we try to preserve systems that are still 
local and diverse, we should also build new or 
recombinant ecologies from global resources, especially 
in order to stabilise degraded lands. 

In your own garden, there are likely to be plants, 
animals, and soil organisms from every major 
landmass and many islands. Jet travel has merely 
accelerated a process already well-established by 
continental drift, bird migration, wind transport, and 
the rafting of debris by water. Everything will, in time, 
either become extinct, spread more widely, or evolve to 
new forms. Each of these processes is happening at 
once, but the rate of extinction and exchange is 
accelerating. Rather than new species, adapted hybrids 
are arising for example as palms, sea grasses, and 
snails, and micro-organisms from many continents 
meet, mix, and produce new accommodations to their 
"new" environments. 

The very chemistry of the air, soil, and water is in 
flux. Metals, chemicals, isotopes, gases, and plastics are 
loose on earth that have never before been present, or 
never present in such form and quantity before we 
made it so. 

It is my belief that we have two responsibilities to 

• Primarily, it is to get our house and garden, our 
place of living, in order, so that it supports us. 

• Secondarily, it is to limit our population on earth, 
or we ourselves become the final plague. 

Both these duties are intimately connected, as stable 
regions create stable populations. If we do not get our 
cities, homes, and gardens in order, so that they feed 
and shelter us, we must lay waste to all other natural 
systems. Thus, truly responsible conservationists have 
gardens which support their food needs, and are 
working to reduce their own energy needs to a modest 
consumption, or to that which can be supplied by local 


TABLE 1.1 


The result ot a unique assembly o! constructs, species, and social systems 
into a unique pattern suited to a specific site and set of occupants. 










Species People 

Materials and Fuels Legal/Financial Structures 


Guilds Community 

Technology Constructs Trusts, Companies, 

Cooperatives, Community 
Credit Unions. 





Water Supply 

Planting patterns 




For best flow, function, and yield whilst 
conserving resources. 


marriage of site constraints 
to people's needs. 




wind, water, forest, or solar power resources. We can 
work on providing biomass for our essential energy 
needs on a household and regional scale. 

It is hypocrisy to pretend to save forests, yet to buy 
daily newspapers and packaged food; to preserve 
native plants, yet rely on agrochemical production for 
food; and to adopt a diet which calls for broadscale 
food production. 

Philosopher-gardeners, or farmer-poets, are 
distinguished by their sense of wonder and real feeling 
for the environment. When religions cease to obliterate 
trees in order to build temples or human artefacts, and 
instead generalise love and respect to all living systems 
as a witness to the potential of creation, they too will 
join the many of us now deeply appreciating the 
complexity and self-sustaining properties of natural 
systems, from whole universes to simple molecules. 
Gardener, scientist, philosopher, poet, and adherent of 
religions all can conspire in admiration of, and 
reverence for, this earth. We create our own life 
conditions, now and for the future. 

In permaculture, this means that all of us have some 
part in identifying, supporting, recommending, 
investing in, or creating wilderness habitats and 
species refuges, the practical way to proceed (outside 
the home garden) is to form or subscribe to institutes 
or organisations whose aims under their legal charter 
are to carry out conservation activities. While the costs 
are low, in sum total the effects are profound. Even the 
smallest garden can reserve off a few square metres of 
insect, lizard, frog, or butterfly habitat, while larger 
gardens and farms can fence off forest and wetland 
areas of critical value to local species. Such areas 
should be only for the conservation of local species. 

Permaculture as a design system contains nothing 
new. It arranges what was always there in a different 
way, so that it works to conserve energy or to generate 
more energy than it consumes. What is novel, and 
often overlooked, is that any system of total common- 
sense design for human communities is revolutionary! 

Design is the keyword of this book: design in 
landscape, social, and conceptual systems; and design 
in space and time. I have attempted a treatment on the 
difficult subject of patterning, and have tried to order 
some complex subjects so as to make them accessible. 
The text is positivistic, without either the pretended 
innocence or the belief that everything will turn out 
right. Only if we make it so will this happen. 

As will be clear in other chapters of this book, the 
end result of the adoption of permaculture strategies in 
any country or region will be to dramatically reduce 
the area of the agricultural environment needed by the 
households and the settlements of people, and to 
release much of the landscape for the sole use of 
wildlife and for re-occupation by endemic flora. 
Respect for all life forms is a basic, and in fact essential, 
ethic for all people. 

_1 A _ 


Lovelock, J. E., Gaia: A Neiv Look at Life on Earth, Oxford 
University Press, 1979. 

Odum, Eugene, Fundamentals of Ecology, W. B. 
Saunders, Toronto, 1971. 

Thomas, Lewis, The Lives of a Cell, The Viking Press, 
Inc., 1974. 


Chapter 2 


The world teeters on the threshold of revolution. 
If It Is a bloody revoluUon It Is all over. The al¬ 
ternative Is a design science revolution... Design 
science produces so much performance per unit 
of resource Invested as to take care of all human 

(Buckminster Fuller) 

All living organisms... are open systems’: that Is 
to say. they maintain their complex forms and 
functions through continuous exchanges of 
energies and materials with their environment. 
Instead of running down' like a mechanical clock 
that dissipates its energy through friction, the 
living organism is constantly building up’ more 
complex substances from the substance It feeds 
on. more complex forms of energies from the 
energies it absorbs, and more complex patterns of 
information... perceptions, feelings, thoughts... 
form the input of its receptor organs. 

(Arthur Koestler, 1967, The Ghost in the Machine) 

Most thermodynamic problems concern closed’ 
systems, where the reactions take place In 
confinement, and can be reversed: an example is 
the expansion and compression of gas in a 
cylinder. But in an open system, energy is 
gained or lost irreversibly, and the system, its 
environment, or both are changed by the inter¬ 
action... the second law of thermodynamics 
[states that] energy tends to dissipate and 
organized systems drift Inevitably towards 
entropy, or chaos. In seeming violation of that 
law. biological systems tend to become 
increasingly complex and efficient. 

( Newsweek, October 24,1977, on the Nobel Prize 
awarded to Ilya Prigogine.) 

Lovelock shows that the biosphere, or Gaia as he 
calls it. actually created those conditions that are 
required for Its support... and systematically 
builds up the stock of materials that it requires to 
move... towards increasng complexity, diversity, 
and stability. 

(Edward Goldsmith, 1981, Thermodynamics or 
Ecodynamics’’, The Ecologist.) 

Man did not weave the web of life, he is merely a 
strand In it. Whatever he does to the web. he 
does to himself... to harm the earth is to heap 
contempt upon the creator... contaminate your 
bed. and you will one night suffocate in your own 

(Chief Seattle, 1854, responding to a U. S. 
government offer to buy Indian land.) 

_ 2A _ 


It is alarming that in western society no popular body 
of directives has arisen to replace the injunctions of 
tribal taboo and myth. When we left tribal life we left 
with it all guides to sensible behaviour in the natural 
world, of which we are part and in which we live and 
die. More to the point, by never having the time or 
commonsense to evolve new or current guiding 
directives, we have forgotten how to evolve 
self-regulating systems. Hence, the call for a society in 
which we are all designers, based on an ethical and 
applied education, with a clear concept of life ethics. 

The Gaia hypothesis, as formulated by James 
Lovelock, is that the earth less and less appears to 
behave like a material assembly, and more and more 
appears to act as a thought process. Even in the 
inanimate world we are dealing with a life force, and 


our acts are of great effect. The reaction of the earth is 
to restore equilibrium and balance. If we maltreat, 
overload, deform, or deflect natural systems and pro¬ 
cesses, then we will get a reaction, and this reaction 
may have long-term consequences. Don't do anything 
unless you've thought out all its consequences and 

Aboriginal cultures used myth to show how unneces¬ 
sary acts and unthinking destruction of elements 
brings about catastrophe and suffering. The usual 
structure of myth has these sequences: 

1 . A willful act of an individual or group. 

2. A transmutation (animate to inanimate or the 
reverse, e.g. Lot's wife turns into a pillar of salt). This 
is by way of a warning. 

3. Invocation of an elemental force (fire, storm, 
earthquake, flood, tidal wave, plague) as a result of any 
set of willful acts. 

4. Necessary atonement by suffering, isolation, 
migration, or death. 

So the act of a child or individual is given a meaning 
which relates to the whole of nature, and rebounds on 
the society. Reared on such myths, we go carefully in 
the world, aware that every unthinking act can have 
awful consequences. 

Because we have replaced nature-based myth with a 
set of fixed prohibitions relating only to other people, 
and unrelated to nature, we have developed 
destructive and people-centred civilisations and 

In life and in design, we must accept that immutable 
rules will not apply , and instead be prepared to be 
guided on our continuing exploration by flexible 
principles and directiivs. 

Thus, this book emphasises self-reliance, responsibil¬ 
ity, and the functions of living things. Within a 
self-regulated system on earth, energy from the sun 
can be trapped and stored in any number of ways. 
While the sun burns, we are in an open system. If we 
don't destroy the earth, open-system energy saving 
will see us evolve as conscious beings in a conscious 

The role of beneficial authority is to return function and 
responsibility to life and to people; if successful, no 
further authority is needed. The role of successful 
design is to create a self-managed system. 

_ 2.2 _ 


Although we can observe nature, living systems do not 
lend themselves to strict scientific definition for two 
reasons. Firstly, life is always in process of change, and 
secondly, life systems react to investigation or ex¬ 
periments. We must always accept, therefore, that 

there will never be "laws" in the area of biology. 

"Hard" science, such as we apply to material systems 
(physics, mathematics, inorganic chemistry), 
studiously avoids life systems, regarding as not quite 
respectable those sciences (botany, /.oology, 
psychology) which try to deal with life. Rigorous 
scientific method deals with the necessity of rigorous 
control of variables, and in a life system (or indeed any 
system), this presumes two things that are impossible: 

1. That you know all variables (in order to control 
some of them and measure others) before you start; or 

2. That you can in fact control all or indeed any 
variables without creating disorder in the life system. 

Every experiment is carried out by people, and the 
results are imparted to people. Thus living things 
conduct and impart knowledge. To ignore life in the 
system studied, one has to ignore oneself. Life exists in 
conditions of flux, not imposed control, and responds 
to any form of control in a new fashion. Living things 
respond to strict control (either by removal of stimuli 
or by constant input of stimuli) by becoming 
uncontrolled, or (in the case of people and rats at least) 
by dysfunction, or by going mad. 

Experiments, therefore, are not decisive, rigid, or 
true findings but an eternal search for the variables 
that have not been accounted for previously. This is 
the equivalent of true believers, in their empirical 
approach to the knowledge of God's name. They 
simply keep chanting variables of all possible names 
until (perhaps) they hit on the right one. Thus does 
science proceed in biological experiments. 

Scientists who "know" and observe, don't usually 
apply their knowledge in the world. Those who "act", 
often don’t know or observe. This has resulted in 
several tragic conditions, where productive natural 
ecosystems have been destroyed to create 
unproductive cultivated systems, breaking every sane 
environmental principle to do so. Energy-efficient 
animals (deer, kangaroo, fish) have been displaced by 
inefficient animal systems (sheep, cattle). Every 
widespread modern agricultural system needs great 
energy inputs; most agriculture destroys basic 
resources and denies future yields. 

As Edward Goldsmith makes clear (’Thermo¬ 
dynamics or Ecodynamics”, The Ecologist, 1981), many 
scientists refuse to consider the function of life in such 
systems. Natural systems disintegrate and decay, 
producing more and more helpless plants, animals, 
and people, and the State or the farmer takes over the 
function of natural processes. (The State becomes the 
father of the orphaned child, the farmer the father of 
the orphaned chicken.) It is only by returning 
self-regulating function and responsibility to living 
things (such as people) that a stable life system can 

Scientific method is one of the ways to know about 
the real world, the world we are part of and live in. 
Observation and contemplative understanding is 
another. We can find out about many things, both 
living and inorganic, by timing, measuring, and 


observ ing them; enough to make calendars, computers, 
clocks, meters, and rulers, but not ever enough to 
understand the complex actions in even a simple living 
system. You can hit a nail on the head, or cause a 
machine to do so, and get a fairly predictable result. 
Hit a dog on the head, and it will either dodge, bite 
back, or die, but it will never again react in the same 
way. We can predict only those things we set up to be 
predictable, not what we encounter in the real world of 
living and reactive processes. 

Ecologists and "whole systems" people struggle to 
understand open and complex systems, even though 
they realise that they too are a part of the system they 
study. In fact, given enough limnologists (those who 
study freshwater lakes and lake organisms), these 
become the most important factor in the spread of lake 
organisms via their boats, boots, and nets! (It is also 
time, I feel, for students of communities to form a 
community of students of communities and keep out of 
everybody else's hair!) 

Overseas aid is perilously close to being a very good 
reason for overseas aid to be necessary, as spies need 
counterspies. I shudder to think that if we train more 
brain surgeons, they must cut open more brains in 
order to support themselves... imagine! I think it fair to 
say that if you submit to poverty, you equip yourself to 
know about poverty, and the same goes for lobotomy. 

There are several ways not to face life: by taking 
drugs, watching television, becoming a fakir in a cave, 
or reading in pure science. All are an abdication of 
personal responsibility for life on earth (including, of 
course, one's own life). Value- and ethic-free lifestyles 
are as aberrant in science as in society. 

It Is the quantlflability of many... scientific 
concepts that have led to their adoption by 
scientists often regardless of the fact that, as 
they are defined, they correspond to nothing 
whatsoever in the world of living things. 

(E. Goldsmith, 1981 Thermodynamics or 
Ecodynamics", The Ecologist.) 

Perverse planning is everywhere obvious: houses 
face not the sun, but rather the road, lawns replace 
gardens, and trees are planted to be pruned and 
tended. Make-work is the rule, and I suspect that most 
theoretical scientists inhabit demented domestic 
environments, just as many psychiatrists are 
inhabitants of mental institutions. 

Scientific (and non-scientific) groups or individuals 
can make progress in finding solutions to specific 
problems. The following approaches do very well 
(designers please note): 

1 . IMPROVING TOOLS, or inventing new tools for 
specific jobs. 

ATIONS on occurrences, or samples of a set of 
phenomena, and sorting them on the basis of likeness- 
unlikeness (by establishing systems and system 
boundaries, categories, and keys to systems). This 

process often reveals common characteristics of 
diverse elements, and leads to an understanding of 
common traits, suggesting (by analogy) strategies in 

3. INSIGHT : the 'Aha!" or "Eureka!" response to 
observation. This, as is well recorded, comes to the 
individual as though by special gift or providence. In 
fact, it is quite probably the end point of 2. 

4. TRIALS: "give it a try and see if it works". This 
empirical approach simply eliminates those things that 
don't work. It does not necessarily establish how or 
why something works, or even if it works in the long 

5. GUESSING: the best guesses are based on trials 
that are already known to work. 

6 . OBSERVING UNIQUE EVENTS and taking note 
of them (the "discovery" of penicillin). 

7. ACCIDENT: trials set up for one reason work in a 
way not predicted or foreseen; compounds made for 
one purpose are applied to another. 

8 . IMITATION: bv testing already-known effects 
(discovered by others). 

9. PATTERNING: by seeing a pattern to events of 
often very different natures, and thus producing 
insights into underlying effects. Often preceded by 2 
above, but rare in science. 

10. COMMONSENSE: often called "management" in 
business and natural systems control. This consists of 
staying with and steering a system or enterprise 
through constant adjustment to a successful conclusion 
or result. It also suits evolving systems, and is the basis 
of continuous change and adjustment. 



Principles differ from dogmas in that there are no 
penalties for error, but only learning from error, which 
leads to a new evolution. Dogmas are rules which are 
intended to force centralised control (often by guilt), 
and it is obvious that every such rule or law represents 
a failure of the social system. It is too late to fail, but 
never too late to adopt sensible principles for our 
guidance, and to throw away the rule book. 

Life Intervention Pnnciple 

In chaos lies unparalleled opportunity for imposing 

creative order. 

Just join with one or two friends to make your way in 
the confusion. Others will follow and learn. 

There is only one law that is offered to us by such 
education as we derive from nature, and that is the law 
of return, which can be stated in many ways: 

Law of Return 

"Whatever we take, we must return", or 


"Nature demands a return for every gift received." 
or "The user must pay." 

We should examine, and ad on, the forms of this law. 
It is the reason why this book carries a tree tax: that we 
may be able to continue in the use of books. It is why 
we must never buy books or newspapers that do not 
tax, nor goods where the manufacturer does not 
recycle or replant the materials of the manufacture. It is 
why we must carefully study how to use our wastes, 
and this includes our body wastes. Put in the form of a 
directive or policy statement, this law would read: 

Every object must responsibly provide for its 
replacement; society must, as a condition of use. 
replace an equal or greater resource than that used. 

Inherent in such a law are the concepts of replanting, 
recycling, durability, and the correct or beneficial 
disposal of wastes. Nature has extreme penalties for 
those who break such laws, and for their descendants 
and neighbours. 

Nor can we deny immanence; if a landscape delights 
us, we should not insult it with castles on peaks, 
roadways, and clear-cuts. We should return the 
pleasure we get from natural prospects, and maintain 
their integrity. It would be pleasant indeed were the 
land around us always to appear welcoming or 
non-threatening. This effect, too, can be created or 
destroyed. There is no reason not to bury our necessary 
constructs in earth, or clothe them with vegetation. If 
we want pleasure in life, then we should preserve the 
life around us. 

Energies enter a system, and either remain or es¬ 
cape. Our work as permaculture designers is to 
prevent energy leaving before the basic needs of the 
whole system are satisfied, so that growth, re¬ 
production, and maintenance continue in our living 

All permaculture designers should be aware of the 
fundamental principles that govern natural systems. 
These are not immutable rules, but can be used as a set 
of directives, taking each case as unique but gaining 
confidence and inspiration from a set of findings and 
solutions in other places and other times. We can use 
the guiding principles and laws of natural systems, as 
formulated by such people as Watt, Odum, and Birch, 
and apply some of them to our consciously-designed 

One such law is the basic law of thermodynamics, as 
restated by Watt< 13 >: 

All energy entering an organism, population or 
ecosystem can be accounted for as energy 
which is stored or leaves. Energy can be 
transferred from one form to another, but it 
cannot disappear, or be destroyed, or created. 
No energy conversion system is ever com¬ 
pletely efficient. 

As stated by Asimov (1970): 

The total energy of the universe is constant 

and the total entropy is increasing. 

Entropy is bound or dissipated energy; it becomes 
unavailable for work, or not useful to the system. It is 
the waters of a mountain stream that have reached the 
sea. It is the heat, noise, and exhaust smoke that an 
automobile emits while travelling. It is the energy of 
food used to keep an animal warm, alive, and mobile. 
Thus, ambient and useful energy storages are 
degraded into less useful forms until they are no 
longer of any use to our system. 

The question for the designer becomes, "How can I 
best use energy before it passes from my site, or 
system?" Our strategy is to set up an interception net 
from "source to sink". This net is a compound web of 
life and technologies, and is designed to catch and 
store as much energy as possible on its way to in¬ 
creasing entropy (as in Figure 2.1). 

Therefore, we design to catch and store as much 
water as possible from the hills before it ends up at its 
"sink" in the quiet valley lake. If we made no attempt to 
store or use it as it passes through our system, we 
would suffer drought, have to import it from outside 
our system, or use energy to pump it back uphill. 

Although the material world can perhaps be 
predictably measured (at least over a wide range of 
phenomena), by applications of the laws of 
thermodynamics, these relate mainly to non-living or 
experimentally "closed systems". The concept of 
entropy is not necessarily applicable to those living, 
open earth systems with which we are involved and in 
which we are immersed. Such laws are more useful in 
finding an effective path through material technologies 
than through a life-complexed world. The key word in 
open systems is "exchange". For example, on the local 
level, cities appear to be "open", but as they return little 
energy to the systems that supply them, and pass on 
their wastes as pollutants to the sea, they are not in 
exchange but in a localised one-way trade with respect 
to their food resource. All cities break the basic "law of 

Life systems constantly organise and create complex 
storages from diffuse energy and materials, accumu¬ 
lating, decomposing, building, and transforming them 
for further use. We can use these effects in the design 
process by finding pathways or routes by which life 
systems convert diffuse materials into those of most 
use. For example, if we have a "waste" such as manure, 
we can leave it on a field. Although this is of 
productive use, we have only achieved one function. 
Alternatively, we can route it through a series of 
transformations that give us a variety of resources. 

First we can ferment it, and distill it to alcohol, and 
secondly route the waste through a biogas digester, 
where anaerobic organisms convert it to methane, of 
use as a cooking or heating gas, or as fuel for vehicles. 
Thirdly, the liquid effluent can be sent to fields, and the 










The designer's work is to sel up useful energy storages in a 
landscape or building (proceeding from State A to State B). Such 
storages, available for increasing yields, are called resources. 


solid sludge fed to worms, which convert it to rich 
horticultural soil. Fourthly, the worms themselves can 
be used to feed fish or poultry. 

Birch states six principles of natural systems: 

1. "Nothing in nature grows forever." 

(There is a constant cycle of decay and rebirth.) 

2. "Continuation of life depends on the maintenance of 
the global bio-geochemical cycles of essential ele¬ 
ments, in particular carbon, oxygen, nitrogen, sulphur, 
and phosphorus." 

(Thus, we need to cycle these and other minor 
nutrients to stimulate grow-th, and to keep the 
atmosphere and waters of earth unpolluted.) 

3. The probability of extinction of populations or a 
species is greatest when the density is very high or 
very low." 

(Both crowding and too few individuals of a 
species may result in reaching thresholds of 

4. "The chance that species have to survive and 
reproduce is dependent primarily upon one or two key 
factors in the complex web of relations of the organism 
to its environment." 

(If we can determine what these critical factors are, 
we can exclude, by design, some limiting factors, 
e.g. frost, and increase others, e.g. shelter, nest 

5. "Our ability to change the face of the earth increases 
at a faster rate than our ability to foresee the 
consequence of such change." 

(Hence the folly of destroying life systems for 
short-term profit.) 

6. "Living organisms are not only means but ends. In 
addition to their instrumental value to humans and 
other living organisms, they have an intrinsic worth." 

(This is the life ethic thesis so often missing from 
otherwise ethical systems.) 

Although these principles are basic and inescapable, 
what we as designers have to deal with is survival on a 
particular site, here and now. Thus, we must study 
whether the resources and energy consumed can be 
derived from renewable or non-renewable resources, 
and how non-renewable resources can best be used to 
conserve and generate energy in living (renewable) 
systems. Fortunately for us, the long-term energy 
derived from the sun is available on earth, and can be 
used to renew our resources if life systems are carefully 
constructed and preserved. 

There are thus several practical design considera¬ 
tions to observe: 

• The systems we construct should last as long as 
possible, and take least maintenance. 

• These systems, fueled by the sun, should produce 
not only their own needs, but the needs of the people 
creating or controlling them. Thus, they are sustain¬ 
able, as they sustain both themselves and those who 
construct them. 

• We can use energy to construct these systems, 
providing that in their lifetime, they store or conserve 

more energy than we use to construct them or to 
maintain them. 

The following are some design principles that have 
been distilled for use in permaculture: 

AGAINST IT. We can assist rather than impede natural 
elements, forces, pressures, processes, agencies, and 
evolutions. In natural successions, grasses slowly give 
way to shrubs, which eventually give way to trees. We 
can actively assist this natural succession not by 
slashing out weeds and pioneers, but by using them to 
provide microclimate, nutrients, and wind protection 
for the exotic or native species we want to establish. 

"If we throw nature out the window-, she comes back 
in the door with a pitchfork" (Masanobu Fukuoka). For 
example, if we spray for pest infestations, we end up 
destroying both pests and the predators that feed on 
them, so the following year we get an explosion of 
pests because there are no predators to control them. 
Consequently, we spray more heavily, putting things 
further out of balance. Unfortunately, all the pests are 
never killed, and the survivors breed more resistent 
progeny (nature's pitchfork!) 

works both ways. It is only how we see things that 
makes them advantageous or not. If the wind blows 
cold, let us use both its strength and its coolness to 
advantage (for example, funneling wind to a wind 
generator, or directing cold winter wind to a cool 
cupboard in a heated house). A corollary of this 
principle is that everything is a positive resource; it is 
up to us to work out how we may use it as such. A 
designer may recognise a specific site characteristic as 
either a problem or as a unique feature capable of 
several uses, e.g. jagged rock outcrops. Such features 
can only become "problems" when we have already 
decided on imposing a specific site pattern that the 
rock outcrop interferes with. It is not a problem, and 
may be an asset if we accept it for the many values it 
possesses. "The problem is the solution" is a 
Mollisonism implying that only our fixed attitudes are 
problems when dealing with things like rock outcrops! 
A friend has included several natural boulders in her 
home, with excellent physical, aesthetic, and economic 
benefit; the builder would have removed them as 
"problems", at great expense. 

choosing a dam site, select the area where you get the 
most water for the least amount of earth moved. 

UNLIMITED. The only limit on the number of uses of a 
resource possible within a system is in the limit of the 
information and the imagination of the designer. If you 
think you have fully planted an area, almost any other 
innovative designer can see ways to add a vine, a 
fungus, a beneficial insect, or can see a yield potential 
that has been ignored. Gahan Gilfedder at the Garden 
of Eden in Australia found an unsuspected market for 
cherimoya seed, required by nurseries as seed stock for 


grafting. This made a resource from a “waste" product 
derived from damaged fruit. 

principle is that "everything makes it own garden", or 
everything has an effect on its environment. Rabbits 
make burrows and defecation mounds, scratch out 
roots, create short swards or lawns, and also creates the 
conditions favourable for weeds such as thistles. 
People build houses, dispose of sewage, dig up soils 
for gardens, and maintain annual vegetable patches. 
We can "use" the rabbit directly as food, to help in fire 
control, to prepare soil for "thistles" (cardoons and 
globe artichokes), and to shelter many native animal 
species in their abandoned burrows. Rabbits maintain 
species-rich moorland swards suited to many orchids 
and other small plants. It is a matter of careful 
consideration as to where this rabbit, and ourselves, 
belong in any system, and if we should control or 
manage their effects or tolerate them. When we 
examine how plants and animals change ecosystems, 
we may find many allies in our efforts to sustain 
ourselves and other species. (See Figure 2.2). 

_ 1A _ 


The energies coming into our system are such natural 
forces as sun, wind, and rain. Living components and 
some technological or non-living units built into the 
system translate the incoming energies into useful 
reserves, which we can call resources. Some of these 
resources have to be used by the system for its own 
purposes (stocks of fish must be maintained to produce 
more fish). An ideal technology should at the very least 
fuel itself. 

The surplus, over and above these system needs, is 
our yield. Yield, then, is any useful resource surplus to 
the needs of the local system and thus available for use, 
export or trade. The way to obtain yield is to be 
conservative in resource use, for energy, like money, is 
much more easily saved than generated. Resource 
saving involves recycling waste, insulating against heat 
loss, etc. Then, we can work out paths or routes to send 
resources on to their next "use point". 

If the aim of functional design is to obtain yields, or 
to provide a surplus of resources, it is as well to be 
clear about just what it is that we call a resource, and 
what categories of resource there are, as these latter 
may affect our strategies of use. In short, we cannot use 
all resources in the same way and to the same ends. 
Ethics of resource use are evolved by knowing about 
the results of resource exploitation. Forests, soils, air, 
water, sunlight, and seeds are resources that we all 
regard as part of a common heritage. 

A second category of resource is that which belong 
to us as group, family, or person: those fabricated, 
ordered, or otherwise developed resources that people 
create by their work, and of which a presence or 

absence does not apparently affect the common 
resource. What we create, however, is always made from 
the common resource, so that it is impossible to draw a 
line between these categories. 

What other ways can we look at resources? Let us try 
a use-and-results approach. What happens if we use 
some resources, if we look upon them as a yield? We 
then find that a response or result follows. Resources 

Green browse is an example: if deer do not browse 
shrubs, the latter may become woody and unpalat¬ 
able. Also, a browsed biennial, unable to flower, may 
tiller out and become perennial (e.g. the fireweed 
Erechthites nibbled by wallaby in Tasmania). Seedling 
trees can be maintained at browse height, but if 
ungrazed, "escape" to unbrowsable height and shade 
out other palatable plants. Overgrazing may (by 
damage) cause extinction of palatable selected browse 
and browsers, but underbrowsing may cause similar 
effects. Information is another resource that can 
increase with use. It withers or is outdated if not used. 
Too little impoverishes a system, but when freely used 
and exchanged, it flourishes and increases. 

2. THOSE UNAFFECTED BY USE. In impalpable 
terms, a view or a good climate is unaffected by use. In 
palpable terms the diversion of a part of a river to 
hydroelectric generation or irrigation (the water 
returned to the stream after use), is also unaffected, as 
is a stone pile as mulch, heat store, or water run-off 
collector. A well-managed ecosystem is an example of 
resources unaffected by use. 

NOT USED. For example an unharvested crop of an 
annual, or a grass which could be stored for the winter, 
irruptions of oceanic fish, swarms of bees or 
grasshoppers, ripe fruit, and water run-off during 

4. THOSE REDUCED BY USE. For example a fish or 
game stock unwisely used, clay deposits, mature 
forests, and coal and oil. 

OTHER RESOURCES IF USED. Such as residual 
poisons in an ecosystem, radioactives, super-highways, 
large buildings or areas of concrete, and sewers 
running pollutants to the sea. 

Categories 1 to 3 are those most commonly produced 
in natural systems and rural living situations, and are 
the only sustainable basis of society. Categories 4 and 5 
are as a result of urban and industrial development, 
and if not used to produce permanent beneficial 
changes to the ecosystem, become pollutants (some are 
permanent pollutants in terms of the lifetimes of 

It follows that a sane society manages resources 
categories 1 to 4 wisely, bans the use of resource cate¬ 
gory 5, and regulates all uses to produce sustainable 
yield. This is called resource management, and has 
been successfully applied to some fish and animal 
populations, but seldom to our own lives. Investment 


priorities can be decided on the same criteria, at both 
the national and household level. 

A responsible human society bans the use of 
resources which permanently reduce yields of 
sustainable resources, e.g. pollutants, persistent 
poisons, radioactives, large areas of concrete and 
highways, sewers from city to sea. 

Failure to do this will cause the society itself to fail, so 
that programmes of highway building and city 

expansion, the release of persistent biocides, and loss 
of soil will bring any society down more surely and 
permanently than war itself. Immoral governments 
tolerate desertification and land salting, concreted 
highways and city sprawl, which take more good land 
permanently out of life production than the loss of 
territory to a conqueror. Immorality of this nature is 
termed "progress" and 'growth" to confuse the 
ignorant and to supplant local self-reliance for the 
temporary ends of centralised power. 

The key principle to wise resource use is the 
principle of "enough". This is basic to understanding 





societies in chaos or systems in disorder. Today 
superhighways and overpasses in Massachusetts alone 
need some 400 billion dollars to repair, and the 
collapsing sewer systems of London and New York 
some 80 billions. Neither Massachusetts, London, nor 
New York can raise this money, which shows that an 
unthinking historical development strategy can cripple 
a future society. Today’s luxuries are tomorrow s 

EoQgifllfl Qt Disorder 

Any system or organism can accept only that quantity 
of a resource which can be used productively. Any 
resource input beyond that point throws the system or 
organism into disorder; oversupply of a resource is a 
form of chronic pollution. 

Both an over- and undersupply of resources have 
much the same effect, except that oversupply has more 
grotesque results in life systems than undersupply. To a 
degree, undersupply can be coped with by reduced 
growth and a wider spacing or dispersal of organisms, 
but oversupply of a resource can cause inflated growth, 
crowding, and sociopathy in social organisms. In 
people, both gross over- and under-nutrition are 
common. Ethical resource management is needed to 
balance out the pathologies of famine and obesity. 

_ 23 _ 


Yields can be thought of in immediate, palpable, and 
material ways, and are fairly easily measured as: 

1. PRODUCT YIELD: The sum of primary and 
derived products available from, or surplus to, the 
system. Some of these are intrinsic (or precede design), 
others are created by design. 

2. ENERGY YIELD: The sum of conserved, stored, 
and generated energy surplus to the system, again both 
intrinsic and those created by design. 

Impalpable yields are those related to health and 
nutrition, security, and a satisfactory social context and 
lifestyle. Not surprisingly, it is the search for these 
invisible yields that most often drives people to seek 
good design or to take up life on the land, for "what 
does it benefit a man if he gains the whole world and 
loses his soul?" Thus, we see the invisible yields in 
terms of values and ethics. This governs our concept of 
needs and sets the limits of "enough". Here, we see an 
ethical basis as a vital component of yield. 

Although all systems have a natural or base yield 
depending on their productivity, our concern in 
permaculture is that this essential base yield is 
sustainable. Several factors now operate to reduce the 
yield of natural systems. In the simplest form, this is 
the overuse of energy in degenerative systems due to 
the unwise application of fossil fuel energy. "Poisoning 
by unproductive use" is observable and widespread. 

Thus we must concentrate on productive use, which 
implies that the energy used is turned into biological 
growth and held as basic living material in the global 
ecosystem. Unused, wasted, or frivolously used 
resources are energies running wild, which creates 
chaos, destroys basic resources, and eventually 
abolishes all yield or surplus. 

In design terms, we can find yields from those living 
populations or resources which are the stocks of the 
biologist (the so-called standing crop) or from 
non-living systems such as the climatic elements, 
chemical energy, and machine technology. There is 
energy stored by extinct life as coal, oil, and gas; 
energy left over from the formation of the earth as 
geothermal energy; tides; and electromagnetic and 
gravitational forces. Cosmic and solar energies impinge 
on the earth, and life intercepts these flows to make 
them available for life forms. 

In our small part of the system (the design site) our 
work is to store, direct, conserve, and convert to useful 
forms those energies that exist on, or pass through, the 
site. The total sum of our strategy, in terms of surplus 
energy usefully stored, is the system yield of design. 

Definition of Syste m Yie ld 

System yield is the sum total of surplus energy 
produced by. stored, conserved, reused, or converted 
by the design. Energy is in surplus once the system 
itself has available all its needs for growth, 
reproduction, and maintenance. 

Some biologists may define yield or production in 
more narrow terms, accepting that a forest, lake, or 
crop has a finite upper limit of surplus due to substrate 
conditions and available energy. We do not have to 
accept this, as it is a passive approach, inapplicable to 
active and conscious design or active management 
using, for example, fertilisers, windbreaks, or selected 

Even more narrowly defined is the yield of 
agricultural economists, who regard a single product 
(peaches/ha) as the yield. It may be this approach itself 
itself which is the true limit to yield! 

A true accounting of yield takes into consideration 
both upstream costs (energy) and downstream costs 
(health). The "product yield” may create problems of 
pollution and soil mineral loss, and cost more than it 
can replace. 

The very concept of surplus yield supposes either 
flow through or growth within our system. Coal and 
rock do not have yield in this sense; they have a finite 
or limited product. Only life and flow can yield 
continually, or as long as they persist. Thus the energy 
stocks of any system are the flows and lives within it. 
The flow may exist without life (as on the moon), 
where only technology can intervene to obtain a yield, 
but on earth at least, life is the intervening strategy for 
capturing flow and producing yield. And technology 
depends on the continuation of life, not the opposite. 


Living things, including people, are the only effective 
intervening systems to capture resources on this 
planet, and to produce a yield. Thus, it is the sum and 
capacity of life forms which decide total system yield 
and surplus. 

We have long been devising houses, farms, and cities 
which are energy-demanding, despite a known set of 
strategies and techniques (all well tried) which could 
make these systems energy-producing. It has long 
been apparent that this condition is deliberately and 
artificially maintained by utilities, bureaucracies, and 
governments who are composed of those so dependent 
on the consumption and sale of energy resources that 
without this continuing exploitation they themselves 
would perish. 

In permaculture, we have abundant strategies under 
the following broad categories which can create yields 
instead of incurring costly inputs or energy supply. 


• The creation of a niche in space; the provision of a 
critical resource. 

• The rehabilitation and creation of soils. 

• The diversion of water, and water recycling. 

• The integration of structures and landscape. 


• The selection of low-maintenance cultivars and 
species for a particular site. 

• Investigation of other species for usable yields. 

• Supplying key nutrients; biological waste 
recycling (mulch, manure). 

• The assembly of beneficial and cooperative guilds 
of plants and animals. 

Sgatifll an<I Cofligurational: 

• Annidation of units, functions, and species 
(annidation is a design or pattern strategy of 'nesting" 
or stacking one thing within another, like a bowl in a 
bowl, or a vine in a tree). 

• Tessellation of units, functions, and species 
(tessellation is the forming or arranging of a mosaic of 

• Innovative spatial geometry of designs as edge 
and harmonics. 

• Routing of materials or energy to next best use. 

• Zone, sector, slope, orientation, and site strategies 
(Chapter 3). 

• Use of special patterns to suit irrigation, crop 
systems, or energy conservation. 


• Sequential annidation (interplant, intercrop). 

• Increasing cyclic frequency. 

• Tessellation of cycles and successions, as in 
browsing sequences. 

Tec hnical: 

• Use of appropriate and rehabilitative technology. 

• Design of energy-efficient structures. 


• Routing of resources to next best use 

• Recycling at the highest level. 

• Safe storage of food product. 

• No-tillage or low-tillage cropping. 

• Creation of very durable systems and objects. 

• Storage of run-off water for extended use. 


• Removing cultural barriers to resource use. 

• Making unusual resources acceptable. 

• Expanding choices in a culture. 

Le gal/Administrative: 

• Removing socio-legal impediments to resource 

• Creating effective structures to aid resource 

• Costing and adjusting systems for all energy inputs 
and outputs. 


• Cooperative endeavours, pooling of resources, 

• Financial recycling within the community. 

• Positive action to remove and replace impeding 

Desig n: 

• Making harmonious connections between com¬ 
ponents and sub-systems. 

• Making choices as to where we place things or 
how we live. 

• Observing, managing, and directing systems. 

• Applying information. 

This approach to potential production is beyond that 
of product yield alone. It is theoretically unlimited in 
its potential, for system yield results from the number 
of strategies applied, what connections are made, and 
what information is applied to a particular design. 

Now we see that yield in design is not some external, 
fixed, immutable quantity limited by circumstances 
that previously existed, but results from our behaviour, 
knowledge, and the application of our intellect, skill, 
and comprehension. These can either limit or liberate 
the concept of yield. Thus, the profound difference 
between permaculture design and nature, is that in 
permaculture we actively intervene to supply missing 
elements and to guide system evolution. 

Limits la Yield 

Yield is nol a fixed sum in any design system. It is the 
measure of the comprehension, understanding, and 
ability of the designers and managers of that design. 

Defined in this way, yield has no known limits, as we 
cannot know all ways to conserve, store, and save 
energy, nor can we fail to improve any system we build 
and observe. There is always room for another plant, 
another cycle, another route, another arrangement, 
another technique or structure. We can thus continually 
shrink the area we need to survive. The critical yield 
strategy is in governing our own appetites! 


Just as we can increase yield, so we can decrease it. 
The perverse aims of some politicians, developers, and 
even religious dogmatists limit yield by disallowing 
certain products as a yield. Just as one's neighbours 
may refuse the snail and eat the lettuce, refuse the 
blackbird and eat the strawberry, so we may only 
’’allow" certain types of toilets, or certain plants in 
gardens or parks. And thus people are the main 
impediment to using their potential yields. 



If we take as a condition the "fencepost-to-fencepost” 
grasslands or crops now developing in the western 
world, and apply the strategies given, then yields will 
increase. How these systems interact raises yield even 
more, but on their own they are sufficiently impressive. 

Wjjtgr .Storage: 

( 12 - 20 % of landscape). 

1. Product increase, e.g. animal protein production 
(water is more productive per unit area than land; fish 
more efficient at food conversion than cattle). 

2. Product increase on land remaining due to: 

• irrigation; and 

• water nutrient quality from, e.g. fish manure. 

3. Interaction, e.g. ducks on water to increase yields 
in and around ponds (e.g. pest and weed control, 

4. Microclimatic buffering due to water bodies (see 
Chapter 5, Climatic Factors). 

Land Form ing: 

1. Product increase due to even irrigation (no dry 
areas or waterlogging). 

2. Land stability due to reduction of soil loss from 
water run-off or salting. 

3. Gravity flow replaces pumped water (depends on 

4. Recycling of water possible. 

SeiLBeandlt io ning. 

1. Product increase due to deeper root penetration. 

2. Water infiltration (zero run-off) due to absorp¬ 

3. Buffering of soil microclimate (see Chapter 8, 

4. Supply of essential nutrients. 

(20-30% of landscape) 

1. Shelter effects, e.g. increase in plant yields, animal 
protein, and microclimate buffering both above and 
below ground. 

2. Increase in carrying capacity due to shrub and tree 

3. Savings on nutrients recycled via legumes and 

4. Intrinsic products of the forest, e.g. nectar for 
honey, seeds, firewood from fallen timber). 

5. Insect and bird escapement, and pest predator 


6. Wildlife corridors. 

S e le c tiy.e.Fa rm Re aff sta t jgp: 

( not industrial forestry) 

1. Increase precipitation due to night condensation, 
water penetration (see Chapter 6, Trees and Their 
Energy Transactions). 

2. Product increase due to superiority of perennials 
over annuals in bulk, energy savings, and length of 
yield (Figure: 1.1). 

3. Increase in rainfall due to trees cross-wind (see 
Chapter 6). 

4. Reduced cost and increased capacity due to 
selected self-forage browse, e.g. drought-proof 
stockfeed, medicinal qualities of some perennial plants. 

5. Reduced cost due to on-farm durable timber, e.g. 
fence posts, construction material. 

6. Reduced carcass loss due to shivering, sweating, 

7. Increased crop production in sheltered areas. 

8. Increased carcass weight due to increased food 
intake in sheltered conditions (not the same as 6. 
above), i.e. on hot days cattle will graze all day when 
they are on shaded pasture, instead of sheltering from 
the sun. 

9. Reduced evaporation from ponds due to less 
wind over water surfaces (see Chapter 5). 
Ma r ke t_and_Process_Strategies: 

1. Selected crop for specialty market for price/ha 
increase, e.g. fresh herbs near a concentration of 

2. Marketing by self-pick, mail order, direct 
dispatch, way-side sale. 

3. Processing to a higher order of product (e.g. seed 
to oil). 

4. Processing to refined order (e.g. crude eucalyptus 
oil to fractions). 

5. Money saved by processing fuels on farm; plus 
sale of surplus fuel. 


1. Market stability gained by farm-link strategy, 
where an urban group contracts to buy specific 
produce from the farmer. 

2. Income from field days and educational courses. 

3. Rental or income from urban visitors e.g. a guest 
house or holiday farm. 

4. Direct investment by city people in a particular 

5. Formation of a local credit union and bank for the 
district, thus recycling money locally. 

6. Vehicle and implement pool with neighbours; 
schedules of sowing and reaping worked out (capital 
saved 90%). 

7. Labour exchange with neighbours. 

8. Produce and marketing cooperatives. 


1. Low or no-tillage farming saves: 

• energy in reduced tillage; 

• soil; 

• water and reduces evaporation; and 

• time between crops. 


To put these into practical terms, I have culled from 
an interview with a farmer (Norm Sims, Weekly Times, 5 
Jan. 1983) statements on savings due to some site 
strategies applied. On land-forming: "We expect to 
double production over the next few years, using half 
the irrigation waters" (4 times benefit); 'Salinity is 
reduced’’. In severe drought: "Pasture production has 
never looked better and water is available'. "It took us 
six days to irrigate what we now do in two...” and, 
"Rather than restricting watering intervals we are 
restricting the area" (aiming to milk 185 cows on 24 ha. 
On grazing rotation and electric fencing: “26 paddocks 
are grazed in a 21 day rotation" (average field of 1.6 ha 
each with a trough water-point for cattle). 

Here, there are these specific strategies in use: 

• laser levelling of fields for even irrigation; 

• water reticulation; 

• water storage and recycling; 

• grazing rotation of 21 days; 

• central access road; 

• crop for concentrated rations grown; and 

• pasture area reduced to give best watering regime. 

It seems obvious from the foregoing that the primary 

and certain increases in crop yield do not just come 
from varietal selections (a fiction promulgated by 
agricultural companies, seed patent holders, 
agricultural researchers, or extension officers), but from 
attention to site design and development, followed by 
wise enterprise selection to suit the (modified) site, 
concurrently with a marketing and processing strategy. 

As these are often permanent or durable strategies, it 
is not in the commercial interest to encourage them, as 
the continuous benefit is to the farmer alone, and the 
role of middlemen and traders is reduced. But, in the 
western world, the 4-6% of us in essential production 
are in fact enslaved, while the remaining 96% are 
deriving secondary or tertiary benefits without 
adequate return to the primary producers. This can 
only result in a weak economy, waste, and 
irresponsibility for life existence based on the 
expectation that the world owes politicians, students, 
and middlemen a living. 

Benefits, like wastes, must be returned or recycled to 
keep any system going. Accumulations of unused 
benefits are predictive of a collapse at production level; 
thence, throughout all tiers of the system. 


The concentration of yields into one short period is a 
fiscal, not an environmental or subsistence strategy, 
and has resulted in a "feast and famine" regime in 
markets and fields, and consequent high storage costs. 
Our aim should be to disperse food yield over time, so 
that many products are available at any season. This 
aim is achieved, in permaculture, in a variety of ways: 

• By selection of early, mid and late season varieties. 

• By planting the same variety in early or 
late-ripening situations. 

• By selection of varieties that yield over a long 


• By a general increase in diversity in the system, so 

• Leaf, fruit, seed and root are all product yields. 

• By using self-storing species such as tubers, hard 
seeds, fuelwood, or rhizomes which can be cropped on 

• By techniques such as preserving, drying, pitting, 
and cool storage. 

• By regional trade between communities, or by the 
utilisation of land at different altitudes or latitudes. 


How yields endure is important, for there are 
unlimited opportunities to use durable yields in terms 
of season or lifetime. 

By a series of preservation strategies, food can be 
stored for days, weeks, or years. Water not open to 
evaporation and pollution, or with natural cleansing 
organisms, will keep indefinitely. Shelters may outlast 
the forests that build them, or can be made of living or 
durable materials such as ivy, concrete, or stone. 
Energy alone (like the food which is part of energy) is 
difficult to store. Batteries leak or decay, heat escapes, 
and insulation breaks down. Only living things, like 
forests, increase their energy store. 

Because of seasonal or diurnal cycles, we should pay 
close attention to storage strategies. Very little famine 
would occur could grains, fish, and fruit available in 
good times be stored for lean times. The strategies of 
food storage are critical. I believe that people should 
therefore mulch their recipe books, which often specify 
out-of-season or not-in-garden foods, and replace 
them with books that stress either low-energy methods 
of food preservation, or how to live easily from your 
garden in season. 


I confess to a rare problem—gynekinetophobia, or the 
fear of women falling on me—but this is a rather mild 
illness compared with many affluent suburbanites, 
who have developed an almost total zoophobia, or fear 
of anything that moves. It is, as any traveller can 
confirm, a complaint best developed in the affluent 
North American, and seems to be part of blue toilet 
dyes, air fresheners, lots of paper tissues, and two 
showers a day. 

It is very difficult, almost taboo, to talk of using 
rabbits, quail, pigs, poultry, or cows in city farms or 
urban gardens in the United States. They are common¬ 
place city farm animals in England, and are ordinary 
village animals in Asia. Australians feel no repulsion 
towards them, and the edible guinea-pig lives 
comfortably in the homes of South Americans. But in 
the USA, no! 

Useful animals are effectively abolished from 
American cities, leaving the field wide open for a host 
of others: pigeons forage the streets, thousands of gulls 


defecate in New York City reservoirs (fresh from the 
garbage piles); gigantic garbage bins are tipped over by 
large, flea-ridden dogs in Los Angeles; rats half the 
size of dogs (and also flea-ridden) are waiting for the 
garbage left by the dogs, and have tunnelled under the 
bus stops in their millions in Washington, D.C. (not far 
from the White House). They in turn are stalked by 
mangy cats, who also keep a desultory eye on the 
billions of cockroaches crawling in most houses. Not to 
mention the flies. 

We will omit the legendary albino alligators of the 
sewers, and the rejected boa constrictors that pop up in 
the blue-rinse toilets. So much wasted food breeds its 
own population of pests. A sensible re-routing of 
edible garbage through a herd of pigs or a legion of 
guinea-pigs would abolish much of this nuisance, and 
a few good Asian restaurants could deal with the cats 
and dogs. The gulls would starve if chickens were fed 
on household wastes, and the besieged American 
might add a very large range of foods to those now 
available in cities. I mention this only to show that 
cultural prejudices can grossly reduce the available 
food resources, and that if we refuse to take sensible 
actions, some gross results can follow, with the bio¬ 
mass of useful foragers such as domesticated animals 
replaced by an equivalent biomass of pests. 



In a fluctuating climatic and market environment, the 
concept of forcing a maximum product yield is courting 
disaster. This is, however, the whole impetus of selling 
(e.g., the "big pumpkin” and "giant new variety” 
advertisements in seed catalogues), or in prizes 
awarded at agricultural shows. Better by far are more 
crop mixes and fail-safe systems that can produce in 
most conditions (wet or dry, cold or hot), or that hold 
constant value as subsistence (potato, taro, arrowroot) 
or have special value (vanilla, quinine, bamboo), or 
high food value per volume (fish, chicken). 

The factors which can increase product yield are 

• Genetic selection; 

• Increased fertiliser (to a limited extent); 

• Increased water (to a limited extent); 

• Decreased competition from other non-beneficial 
species; and 

• Better management in utilisation of yield and of 
harvest, timing, and integration. 

They are the same factors which cause imbalance, as 
the selection of types for a particular yield need not be 
the factor that enables it to produce consistently in field 
field conditions (whether it be feathering to a 
"standard” in a chicken, redness in a rose, or weight in 
a fish). High-producing hens need biennial re¬ 
placement (thus a constant breeding program) and 
may not even set their own eggs, thus needing artificial 
aids. A water and fertiliser-dependent crop is liable to 
collapse when it is water or nutrient stressed, or 

becomes too expensive to maintain in any market 
downturn. To go for one such crop, and so decrease 
diversity, is to decrease insurance for yield if one 
species or variety fails or is susceptible to change. 
Peasant farmers rightly reject advice based on 
maximum yield fallacies, and even more so if they 
share crops with a landlord, for they also value their 
spare time. 

In the case of livestock, forced production is 
eventually limited by insoluble or intractable illnesses, 
so that in high-producing New Zealand herds, 
veterinary costs reach SI 20 per stock unit (for chronic 
illnesses such as facial eczema and white muscle dis¬ 
ease). On less stressed pastures and farms, veterinary 
costs drop away to $20 or so per unit, top-dressing of 
pasture is reduced, and healthier herds give healthier 
yields. In the end, the forcing of product yields creates 
unique and inflexible health problems in plants, soils, 
and animals. Such yields become economically and 
ecologically unsustainable, and a danger to public 
health. 93% of chickens in battery cages develop 
cancers. If we eat cancer, we must risk cancer, for "we 
are what we eat” in a very real sense. 

Insurance of some yield on a sustainable basis is 
better than expensive “feast and famine" regimes. The 
home garden is one such secure approach, where it is 
rare for all crops to fail, because of the innate diversity 
of such a mixed system. In fact, it is commonplace for 
gardeners to find a garden plant or some varieties fail 
in any one season, but no great harm results, as many 
other crops or varieties are available. Thus, species and 
and variety diversity are what people really need. 
Plant Variety Rights legislation, plant patenting, and 
multinational seed resource ownership has had a 
disastrous effect on the availability of hardy, adapted 
local varieties of plants, especially in Europe, where 
some 85% of locally-adapted seed crops have become 
"illegal", or have disappeared from seed company 

There are several paths open to us in design, and the 
least energy path is the one we seek, or evolve towards. 
There are two ways of producing an egg: the first has 
become the normal way in the western world (Figure 
2.3), and the second is the way proposed by 
permaculture systems (Figure 2.4). 

Some ridiculous systems have been evolved in which 
people, machines, time, and energy are expended in 
vast quantities on the chicken, perhaps with the aim of 
maximum product yield, regardless of costs. We can 
short-cut these systems with great gains in personal 
and planetary health, and with a far greater variety of 
yields available for local ecologies. These illustrations 
also bring home the commonsense nature of 
self-regulated systems. 


_ 26 _ 


Cycles are any recurring events or phenomena. They 
have another implication, which is one of diversion. A 
cycle is, if you like, an interruption or eddy in the 
straight-line progression towards entropy. It is the 
special provenance of life to cycle materials. So 
efficiently does this happen that in a tropical forest 
almost all material nutrients are in cycle in life forms. It 
is this very complex cycling in the tropics which 
opened up so many opportunities for yield that 
thousands of species have evolved to take advantage of 

If NICHES are opportunities in space, CYCLES are 
opportunities in time (a time-slot) and both together 
give harbour to many events and species. Geese eat 
grass, digest it, moult, produce waste products, add 
parasites, digestive enzymes, acids and alkalis, and 
defecate. The ground receives the rejecta, the sun 
shines, and rain may fall. Fungi, bacteria, grass roots 
and foliage work on feathers and faeces, and 
re-metabolise them into life. If we reorganise and en¬ 
courage such cycles, our opportunities to obtain yields 
multiply. Every peasant farmer who keeps pigeons (as 
they still do in the Mediterranean borders) knows this 
truth. Here, every thinking farmer builds his own 
phosphate factory, as a pigeon loft. 

Each such cycle is a unique event; diet, choice, 
selection, season, weather, digestion, decomposition, 
and regeneration differ each time it happens. Thus, it is 
the number of such cycles, great and small, that decide 
the potential for diversity. We should feel ourselves 
privileged to be part of such eternal renewal. Just bv 
living we have achieved immortality—as grass, 
grasshoppers, gulls, geese, and other people. We are of 
the diversity we experience in every real sense. 

If, as physical scientists assure us, we all contain a 
few molecules of Einstein, and if the atomic particles of 
our physical body reach to the outermost bounds of the 
universe, then we are all de facto components of all 
things. There is nowhere left for us to go if we are 
already everywhere, and this is, in truth, all we will 
ever have or need. If we love ourselves at all, we 
should respect all things equally, and not claim any 
superiority over what are, in effect, our other parts. Is 
the hand superior to the eye? The bishop to the goose? 
The son to the mother? 

Principle oLCyciic QpcQfLunily 

Every cyclic event increases the opportunity for yield. 

To increase cycling is to increase yield. 

People are built up molecule by molecule, cycling 
through themselves the materials of their environ¬ 
ment: its air, soils, foods, minerals, and pathogens. 
Over time, people create their own local ecology (as do 
wombats and all sedentary animals); their wastes, 
exudae, and rejecta eventually create the very soils in 
which they garden. 'Garbage in, garbage out" applies 

equally to computers and people. We gardeners are 
constantly cycling ourselves, and by a generational 
pattern of adjustment become "eco-compatible" with 
our landscape and climate. We are not the end point of 
evolution but a step on the way, and part of a whole 
sequence of cycles. 

It is the number of such degenerative-regenerative 
cycles, unknowable to us, which determine the number 
of opportunities in the system, and its potential to 
change, mutate, diversify, and reintegrate. Not only 
can we never cross the same river twice, we can never 
see the same view twice, nor know the same system 
twice. Every cycle is a new opportunity. In nature, it is 
our right to die and make way for our successors, who 
are ourselves re-expressed in different forms. 

It is our tolerance of the proliferation of life which 
permits such cycles. Deprived systems, like those 
blasted by biocides, lose most or all opportunity to 
transcend their prior state, and the egg of life is broken, 
degrades, and assumes a lower potential. 

Tribal peoples are very much aware of, and tied to, 
their soil and landscapes, so that their mental and 
physical health depend on these ties being main¬ 
tained. The rest of us have suffered forcible, historic 
dislocations from home sites, and many no longer 
know where home is, although there are new and 
conscious moves to reinhabit the earth and to identify 
with a bioregion as "home." 

Travel itself causes stress and morbidity. Travellers 
both carry and acquire pathogens and spread them to 
other cultures. New settlers bring new species, new 
timetables, and new concepts. Local systems have to 
readjust, or fail. These processes are analagous to the 
disturbance of old ecosystems by new ecological or 
climatic forces. The post-invasion evolution contains 
part of the old and part of the new system, so is itself a 
new assembly with new potentials. Too often, however, 
we have destroyed very productive local ecologies, 
only to replace them with energy-consuming 
"improvements" of our own making. We have assumed 
the role of the creator, and destroyed the creation to do 

Cycling of nutrients is continuous in the tropics, but 
is interrupted wherever drought, cold, or low nutrient 
status reduces the "base opportunity", just as the killing 
of fish stocks reduces the yield. Such cycles are slowed 
or even stopped by climatic factors or by our 

Cycles in nature are diversion routes away from 
entropic ends—life itself cycles nutrients—giving 
opportunities for yield, and thus opportunities for 
species to occupy time niches. 

Cycles, like comets, have schedules or times to occur. 
Some are frequent and obvious like day and night, 
others long-term like sunspot cycles. Both short and 
long cycles are used in phenomenological reckoning by 
aborigines, who use cycle-indicators as time maps. 



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r^a •• 

1ROM 0R6 




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WiS <3 
(t.<. "^fryy & jh 





Time is a resource which can accumulate in eco¬ 
systems. It can be "lost" to an evolving or evolved 
system by setback (adverse disturbance), just about the 
same way as we can set back the hands of a clock. Such 
setbacks are termed deflection states by ecologists. 

Ecosystems, especially those we are in process of 
constructing or destroying, are always proceding to 
some other state of evolution. Left alone, they may 
evolve at their own pace to some unknowable (or 
imaginary) endpoint, which we once called a climax 
state. However, forest climax states are temporary 
events in the long span of geological time. 

Australian studies show that old dune forests lose 
the battle to mobilise nutrients, and begin to show a 
net nutrient loss, aided by rainfall and occasional fire, 
until they begin to recede to a less vigorous shrubbery 
system. Most other (disturbed) forests appear to be 
building, but (if disturbed too often) never reach the 
previous vigour, height, or yield. This is obvious to 
many of us who have seen original, regrowth, and 
second regrowth tree stands. These show signs of 
decay at progressively lower heights, and no doubt 
these too are losing vitality with age. 1 can sympathise. 

Time can work as a rehabilitative resource, for active 
intervention in such successions enables us to analyse 
and to supply key nutrients and soil treatments, if 
needed, to assist maximum forest rejuvenation. 

A second time concept is that of life-time, or the 
"quality time" that we have to enjoy, examine, and 
understand our world. To the interested observer, it 
would seem that life-time is very short indeed for 
those mobile, power-using, bombarded, employed, 
make-work, and busy humans who make up 
non-tribal societies, while many tribal peoples still 
manage to preserve a high quota of the celebrations, 
discussions, contemplations, mutual preening, and 
creative artwork on which many of us "wish we had 
time to spend..." 

This erosion of the lifetimes of people, exacerbated 
by the media and messages of the consumer society, is 
perhaps the most serious effect of that society. 

Life Is too much with us. late and soon 
Getting and gaining, we lay waste our years... 

(W. B. Yeats) 

People so harried that they have no time for anything 
else", may find that time has run out to save 
themselves, their lives, or those of their children. 


Niche is a place to be, to fit in and find food, shelter, 
and room to operate. Many such niches are unfilled 
due to chance factors. Many are wiped out by agri¬ 
culture or urban sprawl. Many can be created. But in 
pursuit of a simple food product, most farmers give no 
place for wildlife, no nesting sites or unbrowsed grass 
for quail or pheasant (both industrious insect eaters). 

and often no time for any intelligent assessment of the 
potential benefits of other species. 

Existence is not only a matter of product yield, but a 
question of appreciating variety in landscape. Evolv¬ 
ing plant systems and existing animals provide niches 
for new species: the cattle egret follows cattle; the 
burrows of rabbits are occupied by possum, bandicoot, 
snakes, frogs, and feral cats; and the growing tree 
becomes a trellis, shade spot, and a host to fungus and 

Every large tree is a universe in itself. A tree offers 
many specialty-forage niches to bird, mammal, and 
invertebrate species. For instance, yellow-throated 
honeyeaters (in Tasmania) search the knot-holes for 
insects, treecreepers the bark fissures, strongbilled 
honeyeaters the rolls of branch bark and hanging strips 
of bark, and blackhcaded honeyeaters the foliage, 
where pardalotes specify the scale insects as their field. 
As for time-sharing, the yellow-throats are permanent 
and territory-holding residents, the treecreepers 
migrants, the strongbills and blackheads roving flock 
species, and all of them scatter as breeding pairs in the 
spring and summer, so that it is rare to find any one 
tree fully occupied at any one time. There is also a 
pronounced post-breeding tendency for several bird 
species to form consociations for foraging and 
travelling in autumn and winter. Five to eight species 
travel together, some (e.g. fly-catchers) gathering 
insects disturbed by the others, with all species 
reacting to the alarm calls of any one species, but some 
species (mynahs for example) acting as sentinels for the 
whole mixed company. 

Here, we see time, space, and functions all used in a 
complex and non-competitive way, and glimpse 
something of the potential for designers to enrich 
human societies providing that no individual or group 
claims a right to sole use at all times for an area. The 
failure of a monoculture to produce, sustain, or persist 
is thus easily explained, as many species are invading 
or trying to use more efficiently the complex resources 
of time and space. 

A combined space-time factor is called a schedule: a 
time to be in that place. Any observer of public park 
use sees the usage change hour by hour. Morning jog¬ 
gers give way to lunch-time office workers, who are 
succeeded by older, retired people playing draughts, 
later displaced by evening entertainment crowds, and 
late at night, the people on the edge of time: the 
semi-legal, the unemployed, and the lonely. Towards 
dawn, only the lame and isolated strollers, often with 
dogs for companions, remain on the streets. 

Many mammals, forced to develop tracks and resting 
places, do not control "areas", but rather time-slots in 
space. My own studies of wild wallaby, urban people, 
and possum show this to be the case. Fighting occurs 
when one is out of schedule, and ceases when that place 
is vacated for use. 

Schedules may run on long cycles, tuned to the level 
of browse or succession of vegetation, e.g. a sequence 
of grazing has been observed for African herds, so that 




All of the above are independent ‘dimensions' ot the total SPATIAL 
system. As well: 

I) As seasonal migrants through the system; 

g) As opportunistic or irruptive visitors in Hoods, plagues, or alter 

h) As permamnent residents of the system 

All ot the above are TIME-SLOTS, further complicated by a 
TIME-SPACE components 

i) As scheduled visitors sharing a 24 hour access to specific sites, 
and occupying nocturnal and diurnal time slots 

((f) - (i) refer mainly to animal species, although all plants will have 
seasonal phases or responses, can invade, or may schedule their 
flowering times). 

As well, the whole system evolves through time, and climate trends or 
disturbances, such as fire, impose a serial mosaic on the site. Almost 
every significant time-space complex will have its unique species 
There is always a way to ennch species diversity in such a system. 



Not only can we fit species into various levels of plant structure, and 
broad ecotones of vegetation and soils, but also season, time of day. 
migration, and scheduling ol SPACE-TIME relationships allows a 
complex use ot vegetative resources by a great variety of animal 
species, such as we see in the natural world. 

In this landscape, plant and animal species can find innumerable 

a) In the vertical structure ot vegetation (I - IV) including a root 

b) Across the aspects, zones, or soil catena variations with slope, 
and with soil water depth. 

c) In the different orders of flow in streams; 

d) Within the different species that occupy specific sites or 

e) At the edges or boundaries of any system 





('ey CUC 
TIME- . 


antelope follow wildebeest follow elephant (or some 
such sequence) for many herd species. 

This suggests that informed graziers, knowing the 
preferences of different species (sheep follow cattle 
follow horses follow goats) can make much better use 
of the basic browse resource by scheduling rotation 
(not to keep one level of browse constant, but to 
dynamically balance levels by species succession). 

Scheduling (the right" to use a particular space at a 
specific time) occurs within species, where dominant 
animals use prime grazing land at prime time, and 
sub-dominants are pushed to the edge of time and 
space, or between species, so that sequences of differ¬ 
ent species use the same area of vegetation at different 
seasons or stages of growth. No individual "owns" the 
area, just a time-space slot (like a chair in a family 
kitchen at dinnertime). In Tasmania, there are two 
prime time activity peaks for wallaby over 24 hours, 
both at night: the main one is crepuscular (just after 
sundown), and the secondary one is auroral (just 
before dawn). This permits digestive and recuperative 
rest periods, denied to weaker animals who cannot 
compete for preferred periods. Within this framework, 
any possum can, by aggression, displace a wallaby at a 
feeding-place. Any individual holds a place only for a 
short time, moving on to contest another area until 
satiated. Thus, the sharing of resources is a complex 
dynamic, but no species or individual has sole rights. 

A human analogy would be that of a sports-ground 
used by different sports groups at times, by gulls or 
rodents whenever sports are not being played, and by 
worms at all times. 

To summarise, we have: 

• Niche in space, or "territory" (nest and forage 

• Niche in time (cycles of opportunity); and 

• Niche in space-time (schedules). 

Between these, there is alw-ays space or time avail¬ 
able to increase turnover. Niches enable better 
utilisation and greater diversity, hence more yield. Of 
all of these niches, schedules are the best strategy for 
fitting in new species of mammals, providing these are 
not territorial species (which try to hold their own 
space at all times), but are chosen from cooperative 
species which yield space when the time is right (see 
Figure 2.5). There are lessons here for people: those 
who try to hold on to all things at all times prevent 
their use by others. 

__ 2.7 


A figure often used to explain how much of a food or 
forage is needed to grow another animal is the trophic 
pyramid. While the pyramid is a useful concept, it is 
very simplistic, and in all but laboratory conditions or 
feed-lot situations, it is unrelated to field reality, and 

may only apply where we actually provide simple food 
to captive species. The field condition is very different 
(Figure 2.6). 

The pyramid is often used to support claims that we 
should all become vegetarians, or herbivores. This is 
perhaps not so far from the truth, but there are 
real-world factors to consider. 1 have shown the 
pyramid and also a direct path (herbage to human) to 
illustrate how we would support more people if we ate 
vegetation. But we need to re-examine this concept for 
people who return their wastes to gardens. There are 
the following factors to consider: 

shown in a pyramid. Instead of simple "trophic levels", 
we have a complex interaction of the same species, 
largely governed not by food habits, but by pasture 
management practices. Such a complex diagram is 
called a food web, and is the normality in field 

sense vegetation eventually "eats" grasshoppers, frogs, 
fish, and people. Not only that, but as an animal grows, 
it returns nutrient to the soil via excreted, moulted, or 
discarded body wastes, and even if the frog eats 10 kg 
of grasshoppers to make one kilo of frog, it doesn't 
(obviously) keep the 10 kg in a bag, but excretes 9 kg or 
more back to earth as manures. This causes more 
vegetation to grow, thus producing more grasshoppers. 
The manure from insect "pests" may be the basis of a 
regenerative future evolution. 

With these obvious feedbacks, the web itself becomes 
much more complex, and it starts to resemble less of a 
one-way staircase (the pyramid) than a series of cyclic 
events; less of a ziggurat and more like a spider's web. 
So that the real position is that waste recycling to 
herbage is the main producer of that herbage. 

3. WHAT OF MATURITY? If our fish (level 4) was a 
carp, and that carp was more than a year or two old, 
then it would probably have reached full size, although 
it may then continue to live for another 80-100 years. 

So now, the carp (at 80 years old and 10 kg weight) 
has eaten 100 x 10 kg = 1000 kg of frogs and insects, 
and has returned 990 kg of digested material per year 
to the pond, to grow more herbage. Thus, in order to 
keep the system in growth, we must be able to 
efficiently crop any level just before maturity is 
reached. We can see that old or mature systems no 
longer use food for growth, but for maintenance. So it is 
with mature fish, frogs, forests, and people. 

Old organisms thus become constant recyclers (food 
in, waste out) and cease to grow, or they even begin to 
lose weight. This is why we try to use only young and 
growing plants and animals for food, if food is scarce. 
An exception is a fruit or nut tree, where we consume 
seed or fruit (seed is an immature tree). 

people normally eat vegetation, and that many people 
eat grasshoppers, frogs, fish, and (at times) other 
people. Even a cow eats grasshoppers as it eats grass, 
and of course every eater ingests large quantities of 






Ule systems are rarely strictly hieractiical as in the pyramid structure 
Most species are omnivorous and all species recycle valuable waste 

products to lower levels ot the trophic ladder Thus, life systems are a 
web or cyclic systems rather than a pyramid. 

bacteria and small animals living on vegetation. "Man 
cannot live by bread alone", unless in a sterile 
laboratory condition! 

As our one-way pyramid is very suspect, so is the 
argument that we should become vegetarians to 
ameliorate the world food shortage problem. Only in 
home gardens is most of the vegetation edible for 
people; much of the earth is occupied by inedible 
vegetation. Deer, rabbits, sheep, and herbivorous fish 
are very useful to us, in that they convert this 
otherwise unusable herbage to acceptable human food. 
Animals represent a valid method of storing inedible 
vegetation as food. If we convert all vegetation to 
edible species, we assume a human priority that is 
unsustainable, and must destroy other plants and 

animals to do so. 

In the urban western world, vegetarianism relies 
heavily on grains and grain legumes (e.g. the soya 
bean). Even to cook these foods, we need to use up 
very large quantities of wood and fossil fuels. Worse, 
soya beans are one of the foods owned ( 100 % of patent 
rights) by a few multinationals. They are grown on rich 
bottomland soils, in large monocultural operations, 
and in 1980-62 caused more deforestation in the USA 
and Brazil than any other crop. Worse still, about 70% 
of the beans were either fed to pigs, or used in industry 
as a base for paint used on motor vehicles! 

Much worse again, grains and grain legumes 
account for most of the erosion of soils in every 
agricultural region, and moreover, very few home 
gardeners in the developed world ever grow grains or 


grain legumes, so that much of what is eaten in the 
West is grown in areas where real famine threatens 
(mung beans from India, chick peas from Ethiopia, 
soya beans from Africa and India). 

Old farmers and my owm great-grandfather had a 
saying that bears some consideration. This was: "We 
will sell nothing from our farm that will not walk or fly 
off." In effect, the farmer was concerned to sell only 
animals, never crops or vegetation, because if the farm 
was to survive without massive energy inputs, animals 
were the only traditional recycling strategy for a 
sustainable export market. 

What does all this mean to concerned and respons¬ 
ible people in terms of their diet and food habits, with 
respect to a sustainable natural system? 

1. Vegetarian diets are very efficient, providing: 

• They are based on easily cooked or easily 

processed crop grown in home gardens; 

• That wastes, especially body wastes, are 

returned to the soil of that garden; and 

• That we eat from where we live, and do not 

exploit others or incur large transport costs. 

2 . Omnivorous diets (any sort of food) make the best 
use of complex natural systems; that we should eat from 
what is edible, at any level (except for other people in 
most circumstances, and under most laws!) 

3. Primarily carnivorous diets have a valid place in 
special ecologies, such as areas of cold, where garden¬ 
ing cannot be a sufficient food base; in areas where 
people gather from the sea; where harsh conditions 
mean reliance on animals as gatherers; and where 
animals can use otherwise-waste products, such as 
vegetable trimmings, scraps, or rejected or spoilt vege¬ 

4. We should always do our energy budgets. 
Whatever we eat, if we do not grow any of our own 
food, and over-use a flush toilet (sending our wastes to 
sea) we have lost the essential soil and nutrients 
needed for a sustainable life cycle. 

While a tropical gardener can be very efficient and 
responsible by developing fruit and vegetable crop 
which needs very little cooking, sensible omnivorism is 
a good choice for those with access to semi-natural 
systems. City people using sewers would be better 
advised to adopt a free-range meat diet than to eat 
grain and grain legumes. Better still, all city waste 
should be returned to the soils of their supply farms. 

Even in our garden, we need to concentrate on cycles 
and routes rather than think in pyramids. Simplistic 
analysis of trophic levels fails to note that some food 
resources are unusable by people, either because the 
energy needed in processing is too much (since some 
products of nature are poisonous or unpalatable 
foods), or because the resources are too scattered to 
repay our collection. Such resources are often 
harvested into useful packages by other species. 
Herons, themselves edible, eat poisonous toadfish, and 
goats will browse thorny and bitter shrubs. Thus we 
can specify these useful conversions before blindly 

eliminating a life element of any type from our diets. 

While it is manifestly immoral to feed edible 
Peruvian fish to hogs in the USA, it may be of great 
value to convert forest acorns (unharvested in the 
USA) to hogs, and let the pilchards and anchovies feed 
the hungry of Peru (which includes the pelicans!) 

The trophic pyramid is valid enough as a conceptual 
model, for we can see that poisons at the base 
concentrate at the top. In fact, the highest level of some 
radioactives and DDT measured are found in mothers' 
milk. We can sec that the generalised or omnivorous 
(non-selective) feeder is buffered from catastrophic 
famine by a complex web of trophic connections, so 
that some losses and some gains accrue to people, 
being generally omnivorous. 

In short, people need to discard fixed ideas, examine 
their kitchen cupboards, and try to reduce food 
imports, waste, and energy loss. A responsible diet is 
not easy to achieve, but the solutions lie very close to 
home. Viva the home gardener! 



There are ecologies on very flat and somewhat 
invariant sites that in the end simplify, or are originally 
simple because that condition itself is not typical of the 
earth's crust, just as a field, levelled, drained, and 
fertilised for a specific crop will not support the species 
that it once did when it varied in micro-elevation, 
drainage, and plant complexities. Other simple natural 
ecologies occur where rapid change can occur (sea 
coasts), or where we deliberately fire or plough on a 
regular basis, so that there is never enough time for a 
diverse system to establish. 

Marshes, swamps, tidal flats, salt-pans, and level 
deserts support less diversity than adjoining hill and 
valley systems, but nevertheless in sum (if species are 
assembled from global environments or from similar 
climatic areas) are still very rich, and, in the case of 
mangrove and tidal marsh, extremely productive 

It is not that a single stand of one mangrove species 
is itself so diverse, it is the mobile species working at 
different stages of decomposition of the mangrove leaf. 
Each of these species in turn feeds others. 

Thus, very simple plant associations may support 
very productive and complex animal associations. 
Mobile species are capable of occupying a great vari¬ 
ety of niches in one mangrove tree or swamp stand, 
from underground to canopy, and of schedules from 
low to high tide. Time and space are needed for tree 
species to evolve a complex stand in such situations, 
and as they are often obliterated and re-established by 
a world-wide change due to a sea level fluctuation, 
relatively little time can be allowed for mangrove 
species to themselves develop and colonise the new, 


and potentially short-term, shoreline. 

Old deserts, like that of Central Australia, may 
exhibit some 3000 species of woody plants, while 
recently desertified areas, like those of southwest Asia, 
may have as few as 150 plants surviving the recent 
changes from forest. We can, in these cases, act as the 
agents of constructive change, bringing species to assist 
local re-colonisation from the world's arid lands. Such 
species will assist in pioneering natural 
reafforestation. This has not generally been our aim, 
and we annually destroy such invaluable species com¬ 
plexes to grow a single crop such as wheat, thus laying 
waste to the future. 

The number of elements in an aggregate or system 
certainly affects its potential complexity, if complexity 
is taken to be the number of functional connections 
between elements. In fact, as Waddington (1977) points 
out, in the case of a single interaction (a conversation) 
between elements, complexity goes up roughly as the 
square of the number of elements: 'Two's company, 
three's a crowd"...and five or six is getting to be a 

This is bad enough, but if we consider the number of 
possible connections to and from an element such as a 
chicken (Figure 3.1), we can see that these potential 
connections depend on the information we have about 
the chicken, so that the complexity of a system 
depends on the information we have about its 
components, always providing that such information is 
used in design. As we cannot know everything, or 
even know more than the approximate categories and 
quantity of things which are (for example) eaten by 
chickens, thus in permaculture we always suppose that 
the chicken is busy making connections itself , about 
which we could not know and, of course, for which we 
could not design. We must simply trust the chicken. 

Thus, in commonsense, we can design for what we 
believe to be essentials, and let the chicken attend to all 
the details, checking at later stages to see that yields 
(our ultimate products) are satisfactory, the chickens 
healthy and happy, and the system holding up fairly 

It is important to concentrate on the nature or value 
of connections betuven elements. In nature, we can rarely 
connect components as easily as a wire or piece of pipe 
can be fixed into place. We do not 'connect'’ the legume 
to the orange tree, the chicken to the seed, or the 
hedgerow to the wind; we have to understand how 
they function, and then place them where we trust they 
will work. They then proceed to do additional tasks 
and to provide other connections themselves. They do 
not confine their functions to our design concepts! 

Evolving complex species assemblies in isolated 
sites, like the Galapagos Islands, may depend more on 
a species-swarm arising from pioneer or survivor 
species than on invaders adapting from borderlands. 
Only when many niches are empty is a species able to 
differentiate and survive without competition; so the 
dodo and Darwin's finches arose. Having arisen, they 
may then well prove to be very useful to other sys¬ 

tems. Unique island species often have functions not 
easily found in continental and crowded ecologies; 
frequently, hardy travelers like reptiles and crus¬ 
taceans take up those niches that, on continents, are 
occupied by species of mammals and birds. 

It is not enough to merely specify the number of 
connections, and not note their value in the system as a 
whole; it may be possible that complex social situ¬ 
ations and cultivated or chance complexity may occur 
in natural systems by introductions or migrations. 
These new events, although increasing complexity, 
may reduce stability with respect to a desirable local 
yield. Thus, where the benign complexity of coopera¬ 
tive organisms is useful, competitive or inharmonious 
complexity is potentially destructive. Again, it is a 
question of matching needs with products, and of the 
values given to connections. 

_ 23 _ 


It follows that order and disorder arise not from some 
remote and abstract energy theory but from actual 
ground conditions or contexts, both in natural and 
designed systems. Entropy is the result of the frame¬ 
work, not the complexity. A jumble of diverse elements 
is disordered. An element running wild or in an active 
destructwe mode (bull in a china shop) is disordered, 
and too few or too many forced connections lead to 

Order is found in things working beneficially together. 
It is not the forced condition of neatness, tidiness, and 
straightness all of which are, in design or energy terms, 
disordered. True order may lie in apparent confusion; it 
is the acid test of entropic order to test the system for 
yield. If it consumes energy beyond product, it is in 
disorder. If it produces energy to or beyond 
consumption, it is ordered. 

Thus the seemingly-wild and naturally-functioning 
garden of a New Guinea villager is beautifully ordered 
and in harmony, while the clipped lawns and pruned 
roses of the pseudo-aristocrat are nature in wild 

Principle of Disorder 

Order and harmony produce energy for other uses. 
Disorder consumes energy to no useful end. 

Neatness, tidiness, uniformity, and straightness signify 
an energy-maintained disorder in natural systems. 



All key living elements may supply many functions in 
a system, but if we try to force too many work 


functions on an element, it collapses. One cannot 
reasonably expect a cow to give milk, raise a calf, 
forage its own food, plough, haul water, and tread a 
com mill. Forcing an element to function, however, is a 
very different proposition from putting it in position 
where its natural or everyday behaviours permit 
benefits to other parts of the system. 

Placed correctly, a tree or chicken experiences no 
stress not common to all trees and chickens about their 
daily business. Further, if we place any of the other 
elements needed close by, the tree or chicken has less 
stress than normal. It is the design approach itself that 
permits components to provide many functions 
without forcing functions (that are not in any case 
inherent) upon that element. The chicken may be busy, 
but not overworked. 

People, too, like to be where their very different and 
complementary capabilities are used rather than being 
forced to either a single function (like a 300-egg-a-year 
chicken or a typist confined to a computer operation in 
an office), or so many functions that they suffer 
deprivation or overload (like our cow above). .Stress, and Harmony 

Stress here may be defined as either prevention of 
natural function, or of forced function. Harmony may be 
defined as the integration of chosen and natural 
functions, and the supply of essential needs. 



Diversity is the number of different components or 
constructs in the system; an enumeration of elements 
and of parts. It has no relationship to connections be¬ 
tween components, and little to the function or the 
self-regulating capacity of any real system (within the 
boundaries of too few or too many components). Thus 
diversity either of components or assemblies does not 
of itself guarantee either stability or yield. Where we 
maintain such diversity, as in our gardens, then this 
may guarantee yield, but if we leave our gardens, they 
will simplify, or simply be obliterated by 
non-maintained and hardy species adapted to that site 
(as is evident in any abandoned garden). 

Thus, our own efforts are an integral part of 
maintaining diversity in a permaculture system. Few 
species grown by people persist beyond the lifetime of 
those species if we leave the situation alone. Australia 
is a country where towns may arise and be abandoned 
to serve a mining or port operation. Where these were 
built in forested areas, they are obliterated by forest in 
30-80 years, with perhaps a few trees such as dates, 
mulberries, and figs persisting in savannah or isolated 
dryland locations. These ’'survivor" trees are important 
to note in planning longer-term stability for that 

Great diversity may create chaos or confusion, 

whereas multiple function brings order and develops 
resources. I believe that a happy medium is to include 
as much diversity in a cultivated ecosystem as it can 
maintain itself, and to let it simplify or complicate 
further if that is its nature. 

Very diverse things, especially such abstract systems 
as competing beliefs, are difficult to make compatible 
with any natural system, or knowledge, so that some 
sorts of dogmatic diversity are as incompatible as a 
chicken and a fox. Although true incompatibility may 
be rare, one should be prepared for it to exist, and an 
intervening neutral component can be introduced, as is 
the case when growing those "bad neighbours" apples 
and walnuts, where it is necessary to intervene with a 
mulberry, which gets along with them both. 

Principle of Stability 

It is not the number of diverse things in a design that 
leads to stabilty. it is the number of beneficial 
connections between these components. 

It follows that adding in a technology or living species 
' just to have it there” has no sense to it. Adding it in to 
supply a need or consume an otherwise wasted 
resource— to do something useful —makes a great deal of 
sense. Often, however, we lack functional information 
on components and may therefore leave out 
technologies or species in designs which would have 
been useful had we known. Thus, 

Information is the critical potential resource. It becomes 
a resource only when obtained and acted upon. 

In the real world, resources are energy storages; in the 
abstract world, useful information or time. Watt m> , in 
his categories of resources, includes time and diversity. 
Diversity of itself is now not seen as a resource, but a 
diversity of beneficial functional connections certainly is a 
resource. Complexity, in the sense of some powerful 
interconnections between species, is what we are really 
seeking in food systems. Such complexity has its own 
rules, and we are slowly evolving those rules as 
recommendations for polycultures (dealt with 
elsewhere in this book under their climatic character¬ 
istics), or as ''guilds" of plants and animals that assist 
each other. 

Peter Moon (New Sientist, 28 Feb. ’85) differentiates 
between richness (the number of species per unit area), 
diversity (the relative abundance of species), and 
evenness (how species contribute to the biomass total). 
He notes that richness may decrease in plants as 
systems age, when shade and competition reduce 
annuals or weaker species, but that richness may then 
increase in animals such as decomposers, due to the 
development of a greater range of niches and 
microclimate (more animals live in ungrazed or uncut 
grasslands, but less plant species survive). 

Richness of tree species has very recently been 
correlated to the energy use of that plant community, 
as measured by evapotranspiration (New Scientist, 22 


Oct ‘87) . Thus species-rich regions are not so much 
correlated to latitude, allied to richness in birds and 
mammals, or as result of prior events such as glaci¬ 
ation or fire, but are essentially linked to the basic 
productivity of the region. Within this broader 
framework, local niches or a range of altitudes can 
create more diversity; such measures refer to present, 
not past, climate. 

Some disturbance or “moderate stress" such as we 
achieve in gardens provides the richest environment. 
We can actively design to allow some undisturbed (low 
stress) islands of vegetation, while mowing or digging 
in other areas (high stress), thus getting the best of both 
worlds in terms of a stress mosaic. We can also be 
active in plant and animal maintenance, increasing or 
decreasing grazing pressures, thus managing species 
abundance locally. 

_ 2 1 12 _ 


The short meaning of stability in an ecosystem is 
self-regulation rather than a climax (end-point) 
stability. Nothing in nature remains forever, not soil or 
hills or forests. For our foreseeable future we can have 
dynamic life-support systems, as tribal people have 
demonstrated to us all over the world, sometimes for 
thousands of years of constructive regulation. 

Thus, stability in ecosystems or gardens is not the 
stability of a concrete pylon; it is the process of 
constant feedback and response that characterises such 
endeavours as riding a bike. We are also in an area of 
uncertainty about the concept of end states or climax in 
systems—the state to which they tend to evolve. It is 
doubtful if any such state ever existed, as inexorable 
climatic change, fire, nutrient leaching, and invasion 
deflect systems from their apparent endpoints. 

Moreover, it is probable that very old systems are 
also fragile, having been long in a state of main¬ 
tenance, and we may see sudden or slow collapse in 
such evolved states. John Seymour ( Ecos, Summer 
' 81 - 82 ), notes the slow loss of nutrients in an old stable 
dune system at Cooloola in Australia. Here, climax is a 
passing phase as the virgin dunes lose nutrient status 
to fire and water filtration to great depths, where 
nutrients become unavailable to trees. Thus, the study 
of very old systems shows a retreat from the "most 
evolved" (greatest biomas) condition unless some new 
factor is introduced (ash from a volcano, fertiliser 
applied by people). 

Daniel Goodman I Quartertly Review Biology, 50(3)1 
notes that “wild fluctuations" may occur in tropical 
forests, or in savannah grasslands. Epidemics of 
pathogens may affect a plant or animal species and 
sadly decrease its numbers. Although these natural 
fluctuations pale beside our own effects on ecosystems, 
such disturbances, providing they affect only a few 
species, are not as severe as persistent nutrient loss (or 

acid rain). 

All these effects are under some human control in a 
developed ecosystem. Protection from fire, positive 
nutrient supply to plants, and long-term evolutions are 
possible in terms of human occupancy. In the longer term, 
however, we too will be gone, and other species will 
arise to replace us (unless we take the earth with us, as 
megalomaniacs would do if we give them that chance: 
"If I can't take it with me. I'm not going....!") Just as it 
was the habit of kings to be buried with their riches, 
horses, and slaves, so modern warlords threaten to 
bury all humanity as they depart. 

_ ^13 _ 


Old systems store up their energy in bulky unpro¬ 
ductive forms, e.g. an old forest has large trunks, roots 
and limbs, and old fish are "on maintenance". Such 
ancient systems composed of large individuals (trees or 
animals) need energy just to maintain their health, and 
thus they can use less of the available sun energy, so 
that flow of energy through the system is less. Therefore 
the yield, or turnover of matter, is less. This too is a 
function of time (ageing). Matter is used up in system 
maintenance, and is not available as yield, or as 
increasing size or weight in life components. 

Against this factor, species diversity (richness) works 
to make the most of incoming energy. 

Carlander has shown that the standing crop 
of fish In different reservoirs is an increasing 
function of the number of species present. 


This is also true of studies in most "wild" systems, 
where the complexity and standing crop are both much 
more than the simple cultivated ecology which 
replaces them. Thus, the clearing of an African veld or 
an Australian savannah of their web of species, and 
their replacement with a few perennial pasture plants 
and beef cattle, or with a single-species pine forest not 
only takes enormous energy but also grossly decreases 
total yields. 

We would do better to try to understand how to 
manage natural yields, and modify such systems by 
management than to replace them with "economic" 
(here economic means monetary rather than energy 
return) systems which impoverish the yield and 
encourage disaster via pests and soil loss. Economics in 
future will inevitably be tied to yield judged on energy 
rather than on monetary return. In the present 
economy, we waste energy to make money. But in the 
very near future, any system which wastes energy 
must fail. 

Pond and hedgerows both slowly gain species as 
they age, probably as a function of natural dispersal 
plus new niche evolution created by other species. This 
continues until the system begins to be overshadowed 
by a few large dominants or hyper-predators whose 


biomass represents an end storage of energy, and a 
decreasing yield in the total system. 

Only local disturbance (fire, flood, death) renews the 
flow of energy through old systems. The time of 
cycling of natural systems may be a very long period, 
but in annual cropping it may be reduced to just one 
season or less. Permaculture thus uses the time 
resource much better than does annual gardening 
alone, and so uses sun energy to better effect. The 
mixed ecology of annuals and perennials maximises 
not only product yield, but also the resourcefulness of 
the men and women who establish, control, and 
harvest, it. It is only in a thoughtless, monetary, and 
doomed economy that we can evolve the concept of 
unemployed and unwanted human beings. 

Death in over-mature systems is thus seen as the 
essential renewal of life, not in the negativistic sense of 
the fatalist, but in a positivistic and natural way. It is 
better that elements die, and are renewed by other 
species, than the system simplifies to extinction. It is 
better for the tribe if its components change than if it 
turns in on itself, ages, and decays as a whole. Life is 
then seen as a preparation for succession and renewal, 
rather than a journey to extinction. 

Time as Watt notes is a resource. Like all resources, 
too much of it becomes counterproductive, and a 
system in which too much time is accumulated 
becomes chronically polluted, as a system in which not 
enough time has accumulated is below peak yield. A 
strawberry seedling and an old strawberry bush are 
equally unproductive, as are the very young and the 
very old in society. As there are age-specific diseases in 
people (whooping cough, prostate hypertrophy) so 
there are age-specific diseases in whole systems, and a 
mixed-age stand is the best insurance against complete 
failure or epidemic disease of this nature. As 
individuals, we have a right to live a responsible life, 
and a right to die. If our efforts to prevent ageing 
succeed, we may produce a crowded, unstable, and 
unproductive society subject to gerontocratic 

_ 2,14 _ 


The Prime Directive of Permaculture: The only 
ethical decision is to take responsibility for our own 
existence and that of our children's. 

Principle of Cooperation: Cooperation, not 
competition, is the very basis of future survival and of 
existing life systems. 

The Ethical Basis of Permaculture: 

1. CARE OF THE EARTH: Provision for all life 
systems to continue and increase. 

2. CARE OF PEOPLE: Provision for people to access 
those resources necessary to their existence. 

SUMPTION: By governing our own needs, we can set 
resources aside to further the above principles. 

Rules of Use of Natural Resources: 

• Reduce waste, hence pollution; 

• Thoroughly replace lost minerals; 

• Do a careful energy accounting; and 

• Make a biosocial impact assessment for long term 
effects on society, and act to buffer or eliminate any 
negative impacts. 

Life Intervention Principle: In chaos lies un¬ 
paralleled opportunity for imposing creative order. 

Law of Return: Whatever we take, we must return, 

Nature demands a return for every gift received, or 
The user must pay. 

Directive of Return: Every object must responsibly 
provide for its replacement. Society must, as a 
conditions of use, replace an equal or greater resource 
than that used. 

Set of Ethics on Natural Systems: 

• Implacable and uncompromising opposition to 
further disturbance of any remaining natural forests; 

• Vigorous rehabilitation of degraded and damaged 
natural systems to a stable state; 

• Establishment of plant systems for our own use on 
the least amount of land we can use for our existence; 

• Establishment of plant and animal refuges for rare 
or threatened species. 

The Basic Law of Thermodynamics las restated by 


"All energy entering an organism, population or eco¬ 
system can be accounted for as energy which is stored 
or leaves. Energy can be transferred from one form to 
another, but it cannot disappear, or be destroyed, or 
created. No energy conversion system is ever com¬ 
pletely efficient.** 

IAs stated by Asimov (1970)1: "The total energy of 
the universe is constant and the total entropy is 

Birch's Six Principles of Natural Systems: 

1. Nothing in nature grows forever. There is a 
constant cycle of decay and rebirth. 

2. Continuation of life depends on the maintenance 
of the global bio-geochemical cycles of essential 
elements, in particular carbon, oxygen, nitrogen, 
sulphur, and phosphorus. 

3. The probability of extinction of populations or a 
species is greatest when the density is very high or 
very low. Both crowding and too few individuals of a 
species may reach thresholds of extinction. 

4. The chance that a species has to survive and 
reproduce is dependent primarily upon one or two key 
factors in the complex web of relations of the organism 
to its environment. 

5. Our ability to change the face of the earth increases 
at a faster rate than our ability to foresee the 
consequence of change. 

6 . Living organisms are not only means but ends. In 
addition to their instrumental value to humans and 
other living organisms, they have an intrinsic worth. 

Practical Design Considerations: 


• The systems we construct should last as long as 
possible, and take least maintenance. 

• These systems, fueled by the sun, should produce 
not only their own needs, but the needs of the people 
creating or controlling them. Thus, they are sustai¬ 
nable, as they sustain both themselves and those who 
construct them. 

• We can use energy to construct these systems, pro¬ 
viding that in their lifetime, they store or conserve 
more energy than we use to construct them or to 
maintain them. 

Mollisonian Permaculture Principles: 

1. Work with nature, rather than against the natural 
elements, forces, pressures, processes, agencies, and 
evolutions, so that we assist rather than impede natural 

2. The problem is the solution; everything works 
both ways. It is only how we see things that makes 
them advantageous or not (if the wind blows cold, let 
us use both its strength and its coolness to advantage). 
A corollary of this principle is that everything is a 
positive resource; it is just up to us to work out how we 
may use it as such. 

3. Make the least change for the greatest possible 

4. The yield of a system is theoretically unlimited. 
The only limit on the number of uses of a resource pos¬ 
sible within a system is in the limit of the information 
and the imagination of the designer. 

5. Everything gardens, or has an effect on its 

A Policy of Responsibility (to relinquish power): 
The role of beneficial authority is to return function 
and responsibility to life and to people; if successful, no 
further authority is needed. The role of successful 
design is to create a self-managed system. 

Categories of Resources: 

1 . Those which increase by modest use. 

2 . Those unaffected by use. 

3. Those which disappear or degrade if not used. 

4. Those reduced by use. 

5. Those which pollute or destroy other resources if 

Policy of Resource Management: A responsible 
human society bans the use of resources which 
permanently reduce yields of sustainable resources, 
e.g. pollutants, persistent poisons, radioactives, large 
areas of concrete and highways, sewers from city to 

Principle of Disorder Any system or organism can 
accept only that quantity of a resource which can be 
used productively. Any resource input beyond that 
point throws the system or organism into disorder; 
oversupply of a resource is a form of chronic pollution. 

Definition of System Yield: System yield is the sum 
total of surplus energy produced by, stored, conserved, 
reused, or converted by the design. Energy is in 
surplus once the system itself has available all its needs 
for growth, reproduction, and maintenance. 

The Role of Life in Yield: Living things, including 

people, are the only effective intervening systems to 
capture resources on this planet, and to produce a 
yield. Thus, it is the sum and capacity of life forms 
which decide total system yield and surplus. 

Limits to Yield: Yield is not a fixed sum in any 
design system. It is the measure of the comprehension, 
understanding, and ability of the designers and 
managers of that design. 

Dispersal of Food Yield Over Time: 

• By selection of early, mid and late season varieties. 

• By planting the same variety in early or late- 
ripening situations. 

• By selection of long-yielding varieties. 

• By a general increase in diversity in the system, so 

• Leaf, fruit, seed and root are all product yields. 

• By using self-storing species such as tubers, hard 
seeds, fuelwood, or rhizomes which can be "cropped 
on demand”. 

• By techniques such as preserving, drying, pitting, 
and cool storage. 

• By regional trade between communities, or by the 
utilisation of land at different altitudes or latitudes. 

Principle of Cyclic Opportunity: Every cyclic event 
increases the opportunity for yield. To increase cycling 
is to increase yield. 

Cycles in nature are diversion routes away from 
entropic ends—life itself cycles nutrients—giving 
opportunities for yield, and thus opportunities for 
species to occupy time niches. 

Types of Niches: 

• Niche in space, or “territory" (nest and forage 

• Niche in time (cycles of opportunity). 

• Niche in space-time (schedules) 

Principle of Disorder Order and harmony produce 
energy for other uses. Disorder consumes energy to no 
useful end. 

Neatness, tidiness, uniformity, and straightness 
signify an energy-maintained disorder in natural 

Principle of Stress and Harmony 

Stress may be defined as either prevention of natural 
function, or of forced function; and (conversely) 
harmony as the permission of chosen and natural 
functions and the supply of essential needs. 

Principle of Stability: It is not the number of 
diverse things in a design that leads to stability, it is the 
number of beneficial connections between these 

Information as a Resource: Information is the 
critical potential resource. It becomes a resource only 
when obtained and acted upon. 

_ 2A5 _ 


Waddington, C. H., Tools for Thought, Paladin, UK, 


Chapter 3 


_3 1 1_ 


Any design is composed of concepts, materials, tech¬ 
niques, and strategies, as our bodies are composed of 
brain, bone, blood, muscles, and organs, and when 
completed functions as a whole assembly, with a 
unified purpose. As in the body, the parts function in 
relation to each other. Permaculture, as a design system, 
attempts to integrate fabricated, natural, spatial, 
temporal, social, and ethical parts (components) to 
achieve a whole. To do so, it concentrates not on the 
components themselves, but on the relationships 
between them, and on how they function to assist each 
other. For example, we can arrange any set of parts and 
design a system which may be self-destructive or 
which needs energy support. But by using the same 
parts in a different way, we can equally well create an 
harmonious system which nourishes life. It is in the 
arrangement of parts that design has its being and 
function, and it is the adoption of a purpose which 
decides the direction of the design. 

Definition of Permaculture Design 

Permaculture design is a system of assembling 
conceptual, material, and strategic components in a 
pattern which functions to benefit life in all its forms. It 
seeks to provide a sustainable and secure place for 
living things on this earth. 

Functional design sets out to achieve specific ends, and 
the prime directive for function is: 

Every component of a design should function in many 
ways. Every essential function should be supported by 
many components. 

A flexible and conceptual design can accept progress¬ 

ive contributions from any direction, and be modified 
in the light of experience. Design is a continuous pro¬ 
cess, guided in its evolution by information and skills 
derived from earlier observations of that process. All 
designs that contain or involve life forms undergo a 
long-term process of change. 

To understand design, we must differentiate it from 
its component parts, which are techniques, strategies, 
materials and assemblies: 

• TECHNIQUE is "one-dimensional” in concept; a 
technique is how we do something. Almost all 
gardening and farming books (until 1950) were books 
on technique alone; design was largely overlooked. 

• STRATEGIES, on the other hand, add the 
dimension of time to technique, thus expanding the 
conceptual dimensions. Any planting calendar is a 
"strategic" guide. Strategy is the use of technique to 
achieve a future goal, and is therefore more directly 

• MATERIALS are those of, for instance, glass, mud, 
and wood. ASSEMBLIES are the putting together of 
technologies, buildings, and plants and animals. 

There are many ways to develop a design on a 
particular site, some of them relying on observation, 
some on traditional skills usually learned in universi¬ 
ties. I have outlined some methods as follows: 

ANALYSIS: Design by listing the characteristics of 
components (3. 2 ). 

OBSERVATION: Design by expanding on direct 
observation of a site (3.3). 

DEDUCTION FROM NATURE: Design by adopting 
the lessons learnt from nature (3.4). 

OPTIONS AND DECISIONS: Design as a selection of 
options or pathways based on decisions (3.5). 

DATA OVERLAY: Design by map overlays (3.6). 

RANDOM ASSEMBLY: Design by assessing the 
results of random assemblies (3.7). 

FLOW DIAGRAMS: Design for workplaces (3.8). 


chicken requires to lead a full life), and BREED 
CHARACTERISTICS (the characteristics of this special 
kind of chicken, whether it be a Rhode Island Red, 
Leghorn, Hamburg, etc). See Figure 3.1. 

A broader classification would have only two cate¬ 
gories: outputs" and "inputs". Outputs are the yields 
of a chicken, inputs are its requirements in order to 
give those yields. Before we list either, we should re¬ 
flect on these latter categories: 

if they are used productively, or can become 
POLLUTANTS if not used in a constructive way by 
some other part of the system. 

INPUTS, NEEDS, or DEMANDS have to be suppl¬ 
ied, and if not supplied by other parts of the system, 
found to satisfy these demands. Thus: 

A POLLUTANT is an output of any system component 
that is not being used productively by any other 
component of the system. EXTRA WORK is the result 
of an input not automatically provided by another 
component of the system. 

As pollution and extra work are both unnecessary 
results of an incompletely designed or unnatural 
system, we must be able to connect our component, in 
this case the chicken, to other components. The 
essentials are: 

• That the inputs needed by the chicken are supplied 
by other components in the system; and 

• That the outputs of the chicken are used by other 
components (including people). 

We can now list the characteristics of the chicken, as 
we know them. Later, we can see how these need to be 
linked to other components to achieve our 
self-regulated system, by a ground strategy of relative 
placement (putting components where they can serve 
each other). 

Primary needs are food, warmth, shelter, water, grit, 
calcium, dust baths, and other chickens. 

Secondary needs are for a tolerable social and 
physical environment, giving a healthy life of moderate 


Primary products are, for instance: eggs, feathers, feather 
dust, manure, various exhaled or excreted gases, 
sound, and heat. 

Derived products are many. From eggs we can make a 
variety of foods, and derive albumen. From feathers 
we can make dusters, insulation, bedding, rope, and 
special manures. Manure is used directly in the garden 
or combined with leaf and stem materials (carbon) to 
supply compost heat. Composted anaerobically, it 
supplies methane for a house. Heat and gases both 
have a use in enclosed glasshouses, and so on. Our list 
of derived products is limited only by lack of specific 
information and by local needs for the products. 

Behaviours: chickens walk, fly, perch, scratch, preen, 
mate, hatch eggs, care for young, form flocks of 20-30 
individuals, and forage. They also process food to form 
primary products and to maintain growth and body 



5 Manure Methane CQi Scratch 

\ t t / * 




Grit _ 
Past - 
Air — 

ONter - 


(Stiver- spang kd 
Hamburgh her|) 

bro set 



Breed Specific 



Analysis of these inputs and outputs are critical to self-governing 

design A deficit in Inputs creates work, whereas a deficit in output 
use creates pollution. 


3. inta nsi.cs 

Instrinsics are often defined as “breed charac¬ 
teristics". They are such factors as colour, form, weight, 
and how these affect behaviour, space needed, and 
metabolism; how climate and soil affect that chicken; 
or what its tolerances or limits are in relation to heat, 
cold, predation, and so on. For instance, white chickens 
survive extreme heat, while thickly-feathered large 
dark chickens survive extreme cold. Heavy breeds 
(Australorps) cannot fly over a 1.2 m fence, while 
lighter breeds (Leghorns) will clear it easily. 

We can add much more to the above lists, but that 
will do to start with (you can add data to any com¬ 
ponent list as information comes in). 


To enable a design component to function, we must 
put it in the right place. This may be enough for a living 
component, e.g. ducks placed in a swamp may take 
care of themselves, producing eggs and meat and 
recycling seeds and frogs. For other components, we 
must also arrange some connections, especially for 
non-living components, e.g. a solar collector linked by 
pipes to a hot water storage. And we should observe 
and regulate what we have done. Regulation may 
involve confining or insulating the component or 
guiding it by fencing, hedging, or the use of one-way 
valves. Once all this is achieved, we can relax and let 
the system, or this part of the system, self-regulate. 

Having listed all the information we have on our 
component, we can proceed to placement and linking 
strategies which may be posed as questions: 

• Of what use are the products of this particular 
component (e.g. the chicken) to the needs of other 

• What needs of this component are supplied by 
other components? 

• Where is this component incompatible with other 

• Where does this component benefit other parts of 
the system? 

The answers will provide a plan of relative placement 
or assist the access of one component to the others. 

We can choose our other components from some 
common elements of a small family farm where the 
family has stated their needs as a measure of 
self-reliance, not too much work, a lot of interest, and a 
product for trade (no millionaire could ask for more!) 
The components we can bring to the typical small farm 

• Structures : House, barn, glasshouse, 

• Constructs : Pond, hedgerow, trellis, fences. 

• Do mestic Anima ls: Chickens, cows, pigs, sheep, 

• Land Use : Orchard, pasture, crop, garden, 
wood lot. 

• Context : Market, labour, finance, skills, people, 
land available, and cultural limits. 

• Assemblies : Most technologies, machines, roads 
and water systems. 

We will not list the characteristics of all of these 
elements here, but will proceed in more general terms. 

In the light of linking strategies, we know where we 
can't put the chicken (in a pond, in the house of most 
societies, in the bank, and so on), but we can put the 
chicken in the barn, chicken-house, orchard, or with 
other components that either supply its needs or 
require its life products. Our criteria for placement is 
that, if possible, such placement enables the chicken to 
function naturally, in a place where its functions are 
beneficial to the whole system. If we want the chicken 
to work for us, we must list the energy and material 
needs of the other elements, and see if the chicken can 
help supply those needs. Thus: 

THE HOUSE needs food, cooking fuel, heat in cold 
weather, hot water, lights, bedding, etc. It gives shelter 
and warmth for people. Even if the chicken is not 
allowed to enter, it can supply some of these needs 
(food, feathers, methane). It also consumes most food 
wastes coming from the house. 

THE GLASSHOUSE needs carbon dioxide for plants, 
methane for germination, manure, heat, and water It 
gives heat by day, and food for people, with some 
wastes for chickens. The chicken can obviously supply 
many of these needs, and utilise most of the wastes. It 
can also supply night heat to the glasshouse in the 
form of body heat. 

THE ORCHARD needs weeding, pest control, 
manure, and some pruning. It gives food (as fruit and 
nuts), and provides insects for chicken forage. Thus, 
the orchard and the chickens seem to need each other, 
and to be in a beneficial and mutual exchange. They 
need only to be placed together. 

THE WOODLOT needs management, fire control, 
perhaps pest control, some manure. It gives solid fuel, 
berries, seeds, insects, shelter, and some warmth. A 
beneficial interaction of chickens and woodlot is 

THE CROPLAND needs ploughing, manuring, 
seeding, harvesting, and storage of crop. It gives food 
for chickens and people. Chickens obviously have a 
part to play in this area as manure providers and 
cultivators (a large number of chickens on a small area 
will effectively clear all vegetation and turn the soil 
over by scratching). 

THEPASTURE needs cropping, manuring, and stor¬ 
age of hay or silage. It gives food for animals (worms 
and insects included). 

THE POND needs some manure. It yields fish, water 
plants as food, and can reflect light and absorb heat. 

In such a listing, it becomes clear that many com¬ 
ponents provide the needs and accept the products of 
others. However, there is a problem. On the traditional 
small farm the main characteristic is that nothing is 
connected to ani/thing else, thus no component supplies 




Villages and farms may contain all the component fo 

harmonious relationships to each other time, energy, and 

..... resources 
are wasted In this figure unplanned and segregated systems all 

self-governance but unless these components are placed in 

demand inputs 








In this figure many elements supply the energy inputs tor others, and 

the system can be largely selt-regulating 


the needs of others. In short, the average farm does not 
enjoy the multiple benefits of correct relative 
placement, or needful access of one system or 
component to another. This is why most farms are 
rightly regarded as places of hard work, and are 
energy-inefficient See Figures 3.2 and 33. 

Now, without inventing anything new, we can redesign 
the existing components to make it possible for each to 
serve others. See Figure 3.4- 3.5. 

Just by moving the same components into a 
beneficial design assembly, we can ensure that the 
chicken, glasshouse or orchard is working for us, not 
us working for it. If we place essential components 
carefully, in relation to each other, not only is our 
maintenance work minimised, but the need to import 
energies is greatly reduced, and we might expect a 
modest surplus for sale, trade, or export. Such surplus 
results from the conversion of "wastes" into products 
by appropriate use. 

The chicken-house heats (and is heated by) the 
glasshouse, and both are heated by the chimney. The 
chickens range in the orchard, providing manure and 
getting a large part of their food from orchard wastes 
and pests, and from interplants of woodlot or forest 
components. A glasshouse also heats the house, and 
part of the woodlot is a forage system and a 

shelter-belt. Thus, sensible placements, minimising 
work, have been made. Market and investment control 
have been placed in the house, together with an 
information service using a computer, which can link 
us to the world. 

Each part of this sort of design will be dealt with in 
greater detail in this book, but a simple transformation 
such as we made from Figure 3.2 to Figure 3.3 is 
enough to show what is meant by functional design. 

A great part of this design can be achieved, as it was 
here, by analytical methods unrelated to any real site 
conditions. Note that before we actually implement 
anything, before we even leave our desk, we have 
developed a lot of good ideas about patterns and 
self-regulatory systems for a family farm. It only 
remains to see if these are feasible on the ground, and if 
the family can manage to achieve them. This is the 
benefit of the analytical design approach: it can operate 
without site experience! This is also its weakness Until 
the chicken is actually heating the greenhouse, 
manuring the orchard, or helping to produce methane 
for the house, our system is just information, or 
potential. Until that chicken is actually in function, we 
have produced no real resources, nor have we solved 
any real problems on our family farm. 


Information as a Resource 

RESOURCES are practical and useful energy 
storages, while INFORMATION is only a potential 
resource, until it is put to use. 

Wc must never confuse the assembling of information 
with making a real resource difference. This is the 
academic fallacy: "I think, therefore I have acted. - ’ 

Note also that we have arrived, analytically, at the 
need for cooperation within the system, and that any 
competition absorbs energy, hence consumes part of our 
slender resources. Our ideal is to allow the free 
expression of all the beneficial characteristics of the 
chicken, so that we avoid conflict and further regulate 
the system we have designed in light of real-life 
experience on the site. 




Unlike the preceding analytic method, this way of 
arriving at design strategies starts on and around the 

site. Short practice at refining field observation as a 
design tool will convince you that no complex of map 
overlays, library, computer data, or remote analysis 
will ever supplant field observation for dependability 
and relevance. 

Observation is not easily directed, and it is therefore 
regarded as largely unscientific and individualistic. 
Process and events, as we encounter them on a real site, 
are never revealed just by maps or other fixed data. Yet 
it is from the observation of processes and events (such 
as heavy rain and subsequent run-off) that we can 
devise strategies of “least change", and so save energy 
and time. No static method can reveal processes or 
dynamic interactions. 

A camera and a notebook are great aids to observ¬ 
ation, allowing a re-examination of information if 
necessary. A good memory for events helps. Video 
recorders are very useful to review processes. 

How do we proceed? As we approach the problem, 
we can adopt any or all of these attitudes: 

APPROACH, in which ”1 wonder why...* may pre-face 
our actual observation. 

• A THEMATIC APPROACH, where we try to ob¬ 
serve a theme such as water, potential energy sources, 
or the conditions for natural regeneration. 




measure, perhaps using equipment, a factor such as 
temperature gradients, wind, or reflection from trees. 

senses as our instruments, trying to be fully conscious 
both of specific details, sensations, and the total 
ambience of the site. 

In order to develop a design strategy, possible 
procedural stages are as follows: 

1. Make value-free and non-interpretative notes 
about what is seen, measured, or experienced, e.g. that 
'moles have thrown up earth mounds on the field." 
Make no guesses or judgements at this stage (this takes 
some discipline but gets a lot of primary data listed). 

2. Later, select some observations which interest you, 
and proceed to list under each of them a set of 
SPECULATIONS as to possible meanings, e.g. (on the 

• That molehills are only conspicuous on fields, 
and may actually occur elsewhere. 

• Or that they occur only on fields. 

• That fields are particularly attractive to moles. 
And so on. Many speculations can arise from one 

observation! Speculations are a species of hypothesis, a 
guess about which you can obtain more information. 
To further examine these speculations, several 
strategies are open to the observer 

3. Confirm or deny speculations by any or all of 
these methods: 

• Library research on moles, and even on allied 
burrowing species (e.g. gophers). 

• Asking others about moles and their field 

• Devising more observations on one particular 
THEME just to test out your ideas. 

• Recalling all you know about moles or allied 
species in other areas or circumstances. 

This process will start to further elaborate your 
knowledge of an existing and specific site characteristic, 
and may already be leading you to the next step: 

4. Examination of all the evidence now to hand. 
Have we evolved any patterns, any mode of opera¬ 
ting? What other creatures burrow in fields and are 
predators, prey, or just good friends of moles? Now, for 
the last decisive step: 

5. How can we find a USE for all this information? 
What design strategies does any of it suggest? For ex¬ 
ample, we may now have found a lot of data on 
burrowers and fields, and look upon the mole (if mole 
it is) as a fine soil aerator and seed-bed provider, and 
therefore to be encouraged— or the very opposite. We 
may have discovered places where moles are 
beneficial, and places where they could well be 
excluded. Or possibly they are best allowed to go their 
way as natural components in the system. Methods of 
mole-control or data on how to prepare moles for 
eating may have surfaced, and so on. 

As the research and observation phase (plus others' 
observations) goes on, the mole will gradually be seen 
to be already connected in one or other way to worms, 
upturned soils, fields, lawns, gardens, pastures, water 
percolation, and even perhaps soil production. Dozens 
of useful strategies may have evolved from your first 
simple observations, and the site begins to design itself. 
You may begin sensible trials to test some of your 

Some cautious trials and further observation will, in 
time, confirm the benefits (or otherwise) of moles in 
the total system or in specific parts of it. A great deal of 
practical information will be gathered, which will carry 
over to other sites and to allied observations. A study 
of earthworms may have co-evolved, and the 
interconnectedness of natural systems has become 

No analytic method can involve one in the world as 
much as observation, but observation and its methods 
need to be practised and developed, whereas analysis 
needs no prior practice and requires less field research 
or first-hand knowledge. As an observer, however, you 
are very likely to stumble on unique and effective 
strategies, and thus become an innovator! 

The uses and strategies derived from observation, 
experience or experiments on site are the basic tools of 
aware, long-term residents. A set of reliable strategies 
can be built up, many of them transferable to other 
locations. Here, we have used nature itself as our 
teacher. That is the greatest value of nature, and it will 
in time supply answers to all our questions. 

Thus, the end result of systematic observation is to 
have evolved strategies for application in design. A 
second and beneficial result is that we have come to 
know, in a personal and involved way, something of 
the totality of the interdependence of natural systems. 

_ 3 A _ 


The impetus that started Masanobu Fukuoka ,3 - 4) on his 
remarkable voyage to natural farming was the sight of 
healthy rice plants growing and yielding in untended 
and uncultivated road verges. If rice can do this 
naturally, he asked, why do we labour to cultivate the 
soil? In time he achieved high- yielding rice 
production on his farm without cultivation, without 
fertilisers or biocides, and without using machinery. 

Via our senses (which include the sensations of the 
skin in relation to pressure, wind chill, and heat), and 
the organised, patterned, or measured information we 
extract from observation, we can discover a great deal 
about natural processes in the region we are 
examining. In order to put our observations about 
nature to use, we need to look at the following: 



We can imitate the structure of natural systems. If we 
have palms, vines, large evergreen trees, an edge' of 
herbaceous perennials, a groundcover of bulbs or 
tubers, and a rich bird fauna in the natural system of 
the region, then we can reconstruct or imitate such a 
system structure on our site, using some native species 
for pioneers, bird forage, or vine supports. We can add 
to this the palms, vines, trees, tubers, and poultry that 
are of great use to our settlement (over that broad 
range of uses that covers food, crafts, medicines, and 

After studying the natural placement of woody 
legumes or windbreak in natural systems, we can 
imitate these in designed systems. We can improve on 
local species by finding out-of-region or exotic species 
even better suited to those roles than those of an 
impoverished or degraded native flora and fauna. 
Certainly, we can carefully select species of a wider 
range of use to settlements than the natural assembly. 


Apart from the structure of natural systems, we need 
most of all to study process. Where does water run? 
How does it absorb? Why do trees grow in some 
special sites in deserts? Can we construct or use such 
processes to suit ourselves? Some of the processes we 
observe are processes "energised" by animals, wind, 
water, pioneer trees or forbs, and fire. How does a tree 
or herb propagate itself in this region? As every design 
is a continuous process, we should most of all try to 
create useful self-generating systems. Some examples 
would be: 

• On Lake Chelan (Washington state, USA), walnuts 
self-generate from seed rolling downhill in the valleys 
of intermittent streams. Similar self- propagation 
systems work for palms in the tropics. Aleurites 
(candle-nut) in Hawaii, and asparagus along sandy 
irrigation channels. Thus, we save ourselves a lot of 
work by setting up headwater plantations and 
allowing these to self-propagate downstream (as for 
willows, Russian olive, and hundreds of water-plant 
species, including taro in unstable flood-water 
lowlands), as long as these are not a problem locally. 

• Birds spread useful bird forages such as elder¬ 
berries, Coprosma, Lycium, autumn olive, pioneer trees 
or herbs, and preferred grains such as Chenopodium 
species. If we place a few of these plants, and allow in 
free-ranging pigeons or pheasants, they will plant 
more. The same applies to dogs or foxes in the matter 
of loquats, bears for small fruits, and cattle for hard 
seeds such as honey locusts. Burrowers and hoarders 
such as gophers will carry bulbs and root cuttings into 
prairie, and jays and squirrels, choughs, or currawongs 
spread oaks when they bury acorns. 

If, in grasslands or old pastures, we see that a 
"pioneer'' such as tobacco bush, a pine, or an Acacia 
provides a site for birds to roost, initiating a soil change 
so that clumps or coppices of forest form there, we can 

use the same techniques and allied species to pioneer 
our food forests, but selecting species of more direct 
use to us. Many native peoples do just this, evolving 
scattered forest nudeii based on a set of pioneer trees, 
termite mounds, compost heaps, and so on. We can 
provide perches for birds to drop pioneer seeds, and so 
set up plant nucleii in degraded lands around simple 
perches placed on disturbed sites. 

• We can provide nest holes so that owls may then 
move in to control rodents, purple martins to reduce 
mosquitoes, or woodpeckers to control codling moth. 
Many nurse plants allow insect predators to 
overwinter, feed, or shelter within our gardens, as do 
small ponds for frogs and rock piles for lizards. If we 
want these aids to pest control, we need to provide a 
place for them. Some of these natural workers are very 
effective (woodpeckers alone reduce codling moth by 

• To limit a rampant plant, or to defeat invasive 
grasses, we need only to look to nature. Nature im¬ 
poses successions and limits on every species, and once 
we know the rules, we can use this succession to limit 
or exclude our problem species. Many soft vines will 
smother prickly shrubs. Browsed or cut out, they allow 
trees to permanently shade out the shrub, or rot its 
seeds in mulch. Kikuyu grass is blocked from 
spreading by low hedges of comfrey, lemongrass, 
arrowroot ( Canna spp.), or nasturtiums. We can use 
some or all of these species at tropical garden borders, 
or around young fruit trees. We can smother rampage¬ 
ous species such as Lantana by vines such as chayote 
(Sechium edulis) and succeed them with palm/legume 
forests, by cutting or rolling tracks and then planting 
legumes, palms, and vines of our choice. Where 
rampageous grasses smother the trees, we set our trees 
out in a protecting zone of 'soft'' barrier plants such as 
comfrey, nasturtium, or indeed any plant we locally 
observe to "beat the grass”, and we surround our 
mulched gardens with belts of such plants. 

There are hundreds of such botanical lessons about 
us. Look long enough, and the methodologies of nature 
become clear. This is design by analogy: we select 
analagous or botanically-allied species for trials. If 
thistles grow around a rabbit warren, then perhaps if 
we disturb the soil, supply urine and manure, and sow 
seed, we will get globe artichokes (and so I have!) Or 
we can pen goats or sheep on a place, then shut them 
out and plant it. It was by such thinking that the idea 
of chicken or pig “tractors" evoled to remove such 
stubborn weeds as nut-grass. Convolvulus, 
onion-weed, and twitch before planting a new 
succession of useful plants. Or we can provide fences 
or pits to trap wind-blown debris (dried leaves, rabbit 
and sheep manures, seagrasses), which can be gathered 
for garden use. And so on... 

All these strategies can be derived from observing 
natural processes, and used consciously in design to 
achieve a great reduction in work, hence energy inputs. 



Gullies, ridgetops, natural shade, the sides of 
multi-storey buildings, and exposed sunny sites all 
demonstrate different opportunities, just as various 
velocities and grades of streams or rock-falls present 
specific niches. We can find a use for each and every 
such special site, whether as an aid to food storage, 
food dehydration, as an energy source in itself, or as a 
site for a special animal or plant. We also create such 
opportunities over time as we grow groves of trees, 
raise earthbanks, build houses, or excavate caves. It is 
in the creation of microclimates that we find a natural 
diversity and richness increasing. Every clump of trees 
invites new species to establish, every shaded area 
provides a refuge from heat, and ever)' stone pile a 
moist and shaded soil site. We can plan such 
evolutions, and plant to take advantage of them, using 
data derived from a close observation of natural 


Life is not all survival in a stable ecosystem. First by 
designing well, and then observing system evolution, 
we gain contemplative and celebratory time. In 
celebration we can incorporate the myths and skills 
that are important to future generations. In contem¬ 
plation we find more refined, profound, or subtle 
insights into good procedures (Fukuoka 3 - 4 ). To 

implement and manage a constructed or natural 
system inevitably leads to a more revelationary 
lifestyle, a more satisfied and contented life, and a 
sense of one's place in nature. 

To become a philosopher is not necessarily to be of 
benefit to the natural world, but to become a designer 
or gardener is to directly benefit nature or society, and 
one will inevitably generate natural ethics and 
philosophies. To become a good designer is to be in 
search of an understanding of nature, and to be content 
with the search itself. It is to design by natural 
example, becoming aware, taking notes, sitting a long 
time in one place, watching the wind behave and the 
trees respond, thrusting your hand into the soil to feel 
it for moisture (it is always more moist on the shade 
side of tussock grasses, for example), and becoming 
sensitive to the processes and sights about you. 

In microcosm and macrocosm, we can learn from the 
world, and these are the very best lessons to adopt. 
There are a thousand lessons to learn, some so obvious 
that we could pinch ourselves for failing to notice 
them. Such an experiential system of design, in broad 
and in detail, is almost obliterated by the classroom, 
the sterile playground, toys, and didactic education. 
The huge information store that is nature is a primary 
reason for its preservation. We can never afford such a 
fine teacher or an equivalent education system that 
operates without cost or bureaucratic involvement. 



\ l Vo 

1 A l\ \\ 

oooox ooxoox 

PRIORITIES Decided by ethics of use. 

STAGES of procedure by urgency, finance, skills, 
resorces available, energy. 

1 1 1 1 II II 

Practical and satisfactory results 

i // 1 / \ \ / \ 



X A deferred, unnecessary, impractical, or 
unethical path. 

0 Possible choices. 



And so on to evolutions decided by experience, 
returns, benefits. 






For a specific site and specific occupants (or clients), a 
design is a sequence of options based on such things 

• Product or crop options. 

• Social investment options (capital available or 

• Skills and occupations (education available). 

• Processing opportunities on or offsite. 

• Market availability, or specific market options. 

• Management skills. 

That is, any design has many potential outcomes, 
and it is above all the stated aims, lifestyle, and re¬ 
sources of the client(s) that decide their options. Any 
sensible design gives a place to start. The evolution of 
the design is a matter for trial, following observation, 
and then acting on that information. 

1 sometimes think that the only real purpose of an 
initial design is to evolve some sort of plan to get one 
started in an otherwise confusing and complex situ¬ 
ation. If so, a design has a value for this reason alone, 
for as soon as we decide to start doing, we learn how to 

The sort of options open to people start with a 
general decision (a distant goal), which is often set by 
ethical considerations (e.g. "care of the earth"). This 
may lead directly to a second set of possible options, of 
which erosion control, minimal tillage, and perhaps 
revegetation of steep slopes are firmly indicated for a 
specific site in the light of this ethic. 

Thus, an option, once decided on, also indicates other 
options, priorities, and management decisions. In 
practical terms, we may also have to consider costs, 
and perhaps decide to generate some short- or long¬ 
term income. This, in turn, may depend on whether we 
maintain a part-time, non-farm income, or (taking the 
leap) gather up our retirement allowance and go to it. 

All of this can be plotted, rather like the decision 
pattern a tree makes as it branches upwards. Some 
options are impractical, or in conflict with other de¬ 
cisions and ethics, and are therefore unavailable. (See 
Figure 3.6). 

Following through the options that arise from either 
our decisions, or the constraints of site and resources, 
we can see an apparently endless series of pathways. 
The process itself is inevitable, in that it leads to a 
series of innovative and practical procedural 
pathways, some of which may be very promising, and 
all of which agree with the ethical, financial, cultural, 
and ground constraints decided by the site and/or its 

As a bonus, not one or two, but several dozen 
options may remain open, and this is always a secure 
position in which to be. In an uncertain world we need 

all possible doors open! 

Options open up or close down on readily available 
evidence or as decision-points are reached. All will 
affect the number and direction of future actions, hence 
the overall design. To a great extent, this approach 
covers the economic and legal constraints not dealt 
with by either of the preceding analytic or 
observational approaches. It is wise, however, to 
implement a limited range of options for trial, or we 
may incur stress and work as a result of taking too 
much on. 

_3 1 6_ 


In design courses at modern colleges, students are 
taught to labour assiduously over maps, overlays on 
those maps, and overlays on the overlays. This ap¬ 
proach should also be considered. However, as a 
methodology, it is at once more expensive, possibly 
more time-consuming, and potentially the most 
confusing of all approaches. Like the system of options, 
it leads to certain inevitable ground placements, and 
perhaps to uneasy compromises not necessarily 
inherent in the preceding methods. The danger here is 
that the map overlays omit minutiae, and can never 
reveal evolutionary processes. 

Where a mapping and hard data approach is 
weakest, however, is that some factors are not able to 
be mapped (ethical, financial, and cultural con¬ 
straints), and that it is very difficult to include those 
site-relevant details revealed by observation, or 
indicated at once by our analytic method of component 
inputs and outputs. Despite this, a good site map 
makes any landscape design (and this is only part of the 
total design) much easier, and far more visual. A good 
map indicates a lot of sensible options and hypotheses 
(dam sites, soil/crop suitability) which can later be 
checked with actual site conditions, available clay for 
dams, existing useful vegetation, threatened habitat 
and so on. 

The danger of the purely analytic and overlay ap¬ 
proaches is that the very remoteness of such systems 
makes flexibility difficult, occasioning unforeseen work 
and expense, which are not incurred by the more 
empirical and flexible "observation" and "option" 
systems. The latter both allow a flexible response to 
fresh conditions. 

_ 3.7 _ 


This is another analytic method, removed from the site 


itself. It is of value in assessing energy flows in the 
system, and is also a generator of creativity. Because it 
is based on a set of essentially random selections, it 
may reveal some very innovative designs. 

The process is as follows: we select and list a set of 
design components, and with them a set of placement 
or connective strategies. If our components are 
arranged in a circle around these "connections ’, we can 
join them up at random, make a sketch of the results, 
and see what it is that we have achieved. This frees us 
from ’ rational" decisions, and forces us to consider 
unusual connections for their value; connections that 
would be inhibited from proposing by our limited 
education, by cultural restraints, or by normal usage. 
(See Table 3.2). 



Storage box 



Yard or 

Animal shelter 









Compost heaps 













TABLE 3.2 


Having laid out a simple diagram, we can select any 
one component and connect it to others, creating 
images for further examination as to their particular 
uses and functions. Some simple examples are: 

• Glasshouse OVER house 

• Storage box IN glasshouse 

• Raft ON pond 

• Glasshouse ON raft 

• House BESIDE pond 

And, using more connections: glasshouse CON¬ 
TAINING compost heap ATTACHED TO house 
BESIDE pond with cave UNDER, containing storages 
boxes with plants IN these. 

We can sketch these, and see just what it is we have 
achieved in terms of energy savings, unique assemb¬ 
lies, special effects for climate, increased yield, compact 
design, or easier accessibility. As we do not usually 
think of these units with respect to their connections, this 
simple design strategy frees us to do so, and to achieve 
innovative results. 

Having illustrated (by way of a diagram) random 
assemblies, we can then think out what would happen 
if we did in fact build them or model them. Rafts can. 

of course, be oriented quickly to suit seasons. Caves are 
cool and ponds in them almost immune from evapora¬ 
tion. Ducks are safe from predators on rafts. Glass¬ 
houses on rafts will warm contained water and create 
thermal storages and currents. Solar cells will light 
caves, and caves below houses supply storage and cool 
or warm air. Trees shade houses, and so on. 

Thus, immune from ridicule and criticism, we can try 
various unlikely combinations and links of 
components (all of which probably exist somewhere), 
and try to assess what we have done in terms of 
function. This is, if you like, working backwards from 
assembly to function to benefits and system 
characteristics. The value of this approach is that it 
frees us to create novel assemblies and to assess them 
before trials. 

Creative solutions may also be arrived at by 
constantly re-examining a problem, and by 
considering every form of solution, including that 
important strategy of doing nothing! (Fukuoka 3 4 ) 

Restate a problem many ways, reverse the traditional 
approaches, and allow every solution to be considered. 
Simple solutions may be found by this process. 

The art of thinking backwards, or in opposites, is often 
very effective in problem-solving. It is easier to drive 
an axle out of a wheel than to knock a wheel off an 
axle, easier to lower a potted vine down a dark shaft 
over a period of months than to grow it up from the 
bottom. So, if we worry away at problems in terms of 
restatements, turning things on their head and stating 
the opposite, we may find that real solutions lie in 
areas free from acquired knowledge and values. 




For designing any special work place, from a kitchen to 
a plant nursery, the preceding methods have limited 
uses. Here, we call in a different method—the "flow 
chart". We imagine how the process flows. In the 
kitchen we take from storage, prepare, cook, serve, and 
gather in the plates and food for waste disposal and 
return to storage. 

Thus the processes follow a certain path. The best 
kitchens are U-shaped or compact, so that least 
movement is necessary. Storages are near the place 
where food, plates, or pots and pans are needed. 
Frequently-used items are to hand on benches, or in 
special niches. Strong blocks, bench tops, or tables are 
built to take the heavy work of chopping and the 
clamping on of grinders and flour mills. We can mark 
such designs out on the ground, and walk around 
these, preparing an imaginary meal, measuring the 
space taken up by trays, pots, and potato storages, and 


so creating an efficient work place. It should also 
involve the placement of traditional items, and agree 
with cultural uses. 

It is advisable to involve an experienced worker in 
any such design, and to research prior designs or new 
aids to design, such as we find in office furniture which 
can be adjusted to the person. I have seen some 
excellent farm buidings such as shearing sheds and 
their associated yards built by worker-designers after 
years of observation and experience. Some people 
specialise in such design for schools, wineries, and golf 
courses. In general, it is mainly work-places which 
need such careful attention. Most other areas in 
buildings are of flexible use, and have the potential for 
multiple function. 

The technique of flow charts is also applicable to 
traffic-ways and transport lines serving settlements, 
where loads or cargoes are to be received and sorted, 
and where schedules or time-place movements are 
integral to the activity. 



Zone and sector analysis is a primary energy- 
conserving placement pattern for the whole site. When 
we come to an actual site design, we must pay close 
attention to locating components relative to the two 
energy sources of the site: 

First, energy available on site: the people, machines, 
wastes, and fuels of the family or society. For these, we 
establish ZONES of use, of access, and of time 

Second, energy entering or flowing through the site: 
wind, water, sunlight and fire may enter the site. To 
govern these energies we place intervening 
components in the SECTORS from which such energies 
arise, or can be expected to enter. We also define 
sectors for views, for wildlife, and for temperature (as 
air flow). To proceed to a discussion of the pattern in its 


We can visualise zones as series of concentric circles, 
the innermost circle being the area we visit most fre¬ 
quently and which we manage most intensively. Zones 
of use are basic to conservation of energy and resources 
on site. We do not have endless time or energy, and the 
things we use most, or which need us often, must be 
close to hand. We plan our kitchens in this way, and we 
can plan our living sites with equal benefit to suit our 
natural movements. 

We should not pretend that any real site will neatly 
accept this essentially conceptual conformation of 
pattern, which will usually be modified by access, site 

characteristics such as slope and soils, local wind 
patterns, and the technical problems of, for example, 
constructing curved fences in societies where title 
boundaries, materials, and even the education 
available is "straight '. 

In zonation, the village or dwelling itself is Zone 0, or 
the origin from which we work. The available energy 
in Zone 0 is human, animal, piped-in, or created on 
site. Whatever the sources, these energies can be 
thought of as available or on-site energies. In order to 
conserve them, and those other essential re-sources of 
work and time, we need to place components as 

ZoneO (the house or the village). 

In this zone belongs good house design, attached 
glasshouse or shadehouse, and the integration of living 
components as sod roof, vines, trellis, potplants, roof 
gardens, and companion animals. In some climates, 
many of these structures are formed of the natural 
environment, and will in time return to it (bamboo and 
rattan, wattle and daub, thatch, and earth-covered or 
sheltered structures). 

Zone 1 

Those components needing continual observation, 
frequent visits, work input, complex techniques 
(fully-mulched and pruned gardens, chicken laying 
boxes, parsley and culinary herbs) should be placed 
very close to hand , or we waste a great deal of time and 
energy visiting them. Within 6 m (20 feet) or so of a 
home, householders can produce most of the food 
necessary to existence, with some modest trade 
requirements. In this home garden are the seedlings, 
young trees for outer zone placement, perhaps mother 
plants" for cuttings, rare and delicate species, the small 
domestic and quiet animals such as fish, rabbits, 
pigeons, guinea pigs, and the culinary herbs used in 
food preparation. Rainwater catchment tanks are also 
placed here. Techniques include complete mulching, 
intensive pruning of trees, annuals with fast 
replacement of crop, full land use, and nutrient 
recycling of household wastes. In this zone, we arrange 
nature to serve our needs. 


This zone is less intensively managed with 
spot-mulched orchards, main-crop beds, and ranging 
domestic animals, whose shelters or sheds may 
nevertheless adjoin Zone 1 or, as in some cultures, be 
integrated with the house. Structures such as terraces, 
small ponds, hedges, and trellis are placed in this zone. 
Where winter forces all people and animals indoors, 
joint accommodation units are the normality, but in 
milder climates, forage ranges for such domestic stock 
as milk cows, goats, or poultry can be placed in Zone 2. 
Home orchards are established here, and less intensive 
pruning or care arranged. Water may be piped from 
Zone 3, or conserved by species selection. 



This area is the "farm" zone of commercial crop and 
animals for sale or barter. It is managed by green 
manuring, spreading manure from Zone 2, and soil 
conditioning. It contains natural or little-pruned trees, 
broadscale farming systems, large water storages, soil 
absorption of water, feed-store or barns, and field 
shelters as hedgerow or windbreak. 

Zone 4 

This zone is an area bordering on forest or wilderness, 
but still managed for wild gathering, forest and fuel 
needs of the household, pasture or range, and is 
planted to hardy, unpruned, or volunteer trees. Where 
water is stored, it may be as dams only, with piped 
input to other zones. Wind energy may be used to lift 
water to other areas, or other dependable technology 

Zone 5 

We characterise this zone as the natural, unmanaged 
environment used for occasional foraging, recreation, 
or just let be. This is where we learn the rules that we 
try to apply elsewhere. 

Now, any one component can be placed in its right 

zone, at the best distance from our camp, house, or 
village. As our very perfect "target" model does not fit 
on real sites, we need to deform it to fit the landscape, 
and we can in fact bring "wedges" of a wilderness zone 
right to our front door: a corridor for wildlife, birds, 
and nature (Figure 3.7). Or we can extend a more 
regularly used zone along a frequently used path (even 
make a loop track to place its components on). 

Zoning (distance from centre) is decided on two 

1. The number of times you need to visit the plant, 
animal or structure; and 

2. The number of times the plant, animal or 
structure needs you to visit it. 

For example, on a yearly basis, we might visit the 
poultry shed: 

• for eggs, 365 times; 

• for manure, 20 times; 

• for watering, 50 times; 

• for culling, 5 times; and 

• other, 20 times. 

Total = 460 visits; whereas one might visit an oak tree 
twice only, to collect acorns. Thus the zones are 
frequency zones for visits", or "time" zones, however 

TABLE 3.3: 






Main design for: 

House climate. 



Small domestic 
stock & orchard. 

Main crop 
forage, stored. 

forage, forestry, 

Establishment of 

sheet mulch. 

Spot mulch and 
tree guards. 

Soil condition¬ 
ing and green 

Soil conditioning 

Pruning and trees 

Intensive cup 
or espallier 

Pyramid and 
built trellis. 

Unpruned and 
natural trellis. 

thinned to 

Selection of trees 

Selected dwarf 
or multi-graft. 

Grafted varieties 
and plants 

seedlings for 
later grafts, 
by browse. 

Thinned to 
varieties, or 

Water provision 

Rainwater tanks, 

wind pumps, 

Earth tank and 
wells, bores. 

Water storage 
fire control. 

Dams, rivers, 
in soils, dams. 


house. storage 

Greenhouse and 
barns, poultry 

Feed store, field 

Field shelter 
grown as 
and woodlot 


Stored or 
generated by 

In part affected 
by other species. 

As for II. 

Arising from 









you like to define them. The more visits needed, the 
closer the objects need to be. As another example, you 
need a fresh lemon 60-100 times a year, but the tree 
needs you only 6-12 times a year, a total of 66 to 112 
times. For an apple tree, where gathering is less, the 
total may be 15 times visited. Thus, the components or 
species space themselves in zones according to the 
number of visits we make to them annually. 

The golden rule is to develop the nearest area first, get 
it under control, and then expand the perimeter. A 
single perimeter will then enclose all your needs. 

Too often, the novice selects a garden away from the 
house, and neither reaps the plants efficiently, nor cares 
for them well enough. Any soil, with effort and the 
compost from the recycling of wastes, will grow a good 
garden, so stay close to the home. 

Let us think of our zones in a less ordered way, as 
was well described by Edgar Anderson for Central 
Honduras (Anderson, E., 1976): 

Close to the house and frequently more or less 
surrounding It Is a compact garden-orchard 
several hundred square feet In extent. No two 
of these are exactly alike. There are neat 
plantations more or less grouped together. 
There are various fruit trees (nance, citrus, 
mellas. a mango here and there, a thicket of 
coffee bushes In the shade of the larger 
trees)... There are tapioca plants of one or two 
varieties, grown more or less In rows at the 
edge of the trees. Frequently there are patches 
of taro: these are the framework of the 
garden- orchards. Here and there In rows or 
patches are corn and beans. Climbing and 
scrambling over all are vines of various 
squashes and their relatives: the chayote 
(choko) grown for the squashes, as well as its 
big starchy root. The luffa gourd. Its skeleton 
used for dishrags and sponges. The cucurbits 
clamber over the eaves of the house and run 
along the ridgepole, climb high in the trees, or 
festoon the fence. Setting off the whole garden 
are flowers and various useful weeds (dahlias, 
gladioli, climbing roses, asparagus fern, 
cannas). Grain amaranth is a sort of 
encouraged weed that sows itself.’ 

Around the "dooryard gardens" described above, 
Anderson notes the fields (in Mexico) "dotted here and 
there with volunteer guavas and guamuchiele trees, 
whose fruit was carefully gathered. Were they orchards 
or pastures? What words are there in English to 
describe their groupings?" 

Anderson is contrasting the strict, ordered, linear, 
segmented thinking of Europeans with the productive, 
more natural polyculture of the dry tropics. The order 
he describes is a semi-natural order of plants, in their 
right relationship to each other, but not rigorously 
separated into various artificial groups. More than that. 

the house and fence form essential trellis for the 
garden, so that it is no longer clear where orchards, 
field, house and garden have their boundaries, where 
annuals and perennials belong, or indeed where 
cultivation gives way to naturally-evolved systems. 

Monoculture man (a pompous figure I often imagine 
to exist, sometimes fat and white like a consumer, 
sometimes stern and straight like a row-crop farmer) 
cannot abide this complexity in his garden or his life. 
His is the world of order and simplicity, and therefore 

When thinking of placing components into zones, 
remember that intrinsic properties and species- 
specific yields are available from a component 
wherever it is placed (all trees give shade), so that we 
don’t include these "intrinsics" in assessing function in 

Place a component in relation to other components or 
functions, and for more efficient use of space or 
nutrient. Look for products that serve special needs not 
otherwise locally available. 

The amount of management we must always provide 
in a cultivated ecosystem is characterised by conscious 
placement, establishment, guidance, and control 
energies, akin to the adjustments we normally make to 
our environment as we traverse it on our daily tasks. 



Next in a permaculture design, we consider the wild 
energies, the "elements" of sun, light, wind, rain, 
wildfire, and water flow. These all come from outside 
our system and pass through it: a flow of energies 
generated elsewhere. For these, we plan a "sector" 
diagram based on the real site. 

Our sectors are more site-specific than are the 
conceptualised zones. They outline the compass 
directions from which we can expect energy or other 
factors. Some factors we may invite in to our homes; 
we need sunlight for technologies and plant growth. 

Some we may exclude (such as an unpleasant view of a 
junkyard). More commonly, we plan to regulate such 
factors to our advantage, placing our zonal 
components to do so. 

Whereas settlement or house is the ground zero for 
zones, it is the through point for sectors. Energies from 
outside can be thought of as so many arrows winging 
their way towards the home, carrying both destruc-tive 
and beneficial energies; we need to erect shields, 
deflectors, or collectors. Our choice in each and every 
sector is to block or screen out the incoming energy or 
distant view, to channel it for special uses, or to open 


out the sector to allow, for example, maximum 
sunlight. We guard against catastrophic fire, wind, or 
flood by protective embankments, dense trees, ponds, 
roads, fences, or stone walls, and we likewise invite in 
or exclude free-ranging or undomesticated wildlife by 
placements of forage systems, fences, nest boxes, and 
so on. Thus we place hedges, ponds, banks, walls, 
screens, trellises, hedgerows or any other component of 
design to manage incoming energy. 

If you like, we place our components in each zone as 
though zones could be rotated about Zone 0. For any 
one component, it stops rotating when it is working to 
govern energies in the sector diagram. Thus, by 
"revolving" our zones, we find a place where our 
selected component (a tree, fence, pond, wall, or 
animal shed) works to govern sector factors. Given that 
we have both zone and sector energies controlled, then 
our component is well placed. Then we combine the 
two diagrams to make a spiderweb of placements, 
putting every main system in its right place in terms of 
energy analysed on the site (Figure 3.10). 

To sum up, there should be no tree, plant, structure, 
or activity that is not placed according to these criteria 
and the ground plan. For instance, if we have a pine 
tree, it goes in Zone 4 (infrequent visits) away from the 
fire danger sector (it accumulates fuel and bums like a 
tar barrel), TOWARDS the cold wind sector (pines are 
hardy windbreaks), and it should also bear edible nuts 
as forage. 

Again, if we want to place a small structure such as a 
poultry shed, it should BORDER Zone 1 (for frequent 
visits), be away from the fire sector, BORDER the 
annual garden (for easy manure collection), BACK 
ONTO the forage system, possibly ATTACH to a 
greenhouse, and form part of a windbreak system. 

There is no mystery nor any great problem in such 
commonsense design systems. It is a matter of bringing 
to consciousness the essential factors of active plan¬ 
ning. To restate: 

The Basic Energy-ConservinaRulas 

Every element (plant, animal or structure) must be 
placed so that it serves at least two or more functions. 
Every function (e.g. water collection, lire protection) is 
served in two or more ways. 

With the foregoing rules, strategies, and criteria in 
mind, you can't go far wrong in design. 

Placement Principle 

If broad initial patterning is well analysed, and good 
placements made, many more advantages than we 
would have designed for become obvious. 

Or. if we start well, other good things naturally follow on 
as an unplanned result. 

This is the broad pattern approach. Given that the 
scene has been set, observation comes into play to 
evolve other pattern strategies. If we watch just how 
our animals move, how winds vary, or how water 

flows, we can evolve guiding patterns that achieve 
other desirable ends, e.g. making animals easy to 
muster, bringing them to sites where their manure is 
needed, steering cool winds to ameliorate excess heat 
input or to direct them to wind turbines, and directing 
water to where it is needed in our system. 


No site is quite flat, and many have irregular 
configurations; thus our neat spider webs of zone and 
sector overlays are distorted by a more realistic 
landscape. To use these irregularities to our advan¬ 
tage, we need to further consider these factors: 

With zones and sectors sketched in on the ground 
plan, slope analysis may proceed. High and low access 
roads, the former for heavy cargo or mulch, the latter 
for fire control, can now be placed. Provision for 
attached glasshouse, hot air collectors, reflection pond, 
solar pond, and shadehouse should be made at all 
homestead sites where climatic variation is 

Slope determines the unpowered flow of water from 
source to use point, and slope and elevation will per¬ 
mit the placement of hot air or hot water collectors 
below their storages, where the thermosiphon effect 
can operate without external energy inputs. The simple 
physics of flow and thermal movements can be applied 
to the placement of technological equipment e.g. solar 
hot water panels, taking advantage of slope. Where no 
slope exists, towers for water tanks and hollows for 
heat collectors (or solar ponds) can be raised or 
excavated for the same effect. 

However, in the normal humid landscape (where 
precipitation exceeds evaporation), hill profiles 
develop a flattened "S" curve that presents 
opportunities for placement analysis of components 
and systems, as per Figure 3.11. 

The ancient occupied ridgeways of England testify to 
the commonsense of the megalithic peoples in land¬ 
scape planning, but their present abandonment for 
industrial suburbs in flatlands does little credit to the 
palaeolithic planning of modern designers. The 
difference may be that the former planned for 
themselves, while the latter design for "other people". 

Slope gives immense planning advantages There is 
hardly a viable traditional human settlement that is not 
sited on those critical junctions of two natural 
ecologies, whether on the area between foothill forests 
and plains, or on the edge of plain and marsh, land and 
estuary, or some combination of all of these. Planners 
who place a housing settlement on a plain, or on a 
plateau, may have the "advantage' of plain planning, 
but abandon the inhabitants to failure if transport fuels 
dry up. They then have to depend on the natural 
environment for their varied needs but have only a 
monoultural landscape on which to do so. Successful 
and permanent settlements have always been able to 
draw from the resources of at least two environments. 


Similarly, any settlement which (ails to preserve natural 
benefits, and, for example, clears all forests, is bent on 
eventual extinction. 

The descending slopes allow a variety of aspects, 
exposures, insolation, and shelter for people to 
manage. Midslope is our easiest environment, the 
shelter of forests at our back, the view over lake and 
plain, and the sun striking in on the tiers of productive 
trees above and below. Figure 3.11 shows a broad 
landscape profile, typical of many humid tropical to 
cool climates, which we can use as a model to demon¬ 
strate some of the principles of landscape analvsis. 

On the high plateaus (A) or upper erosion surface, 
snow is stored, and trees and shrubs prevent quick 
water run-off. The headwaters of streams seek to make 
sense of a sometimes indefinite slope pattern, giving 
way to the steep upper slopes (B), rarely (or 
catastrophically) of use to agriculture, but un¬ 
fortunately often cleared of protecting forest and 
subject to erosion because of this. 

The lower slopes (C) are potentially very productive 
mixed agricultural areas, and well suited to the 
structures of people and their domestic animals and 
implements. Below this are the gently- descending 
foothills and plains (D) where cheap water storage is 
available as large shallow- dams, and where extensive 
cropping can take place. 

This simplified landscape should dictate several 
strategies for permanent use, and demands of us a 
careful analysis of techniques to be used on each area. 

The main concern is water, as it is both the chief 
agent of erosion and the source of life for plants and 
animals. Thus the high plateau is a vast roof where rain 
and snow gather and winds carry saturated cloud to 
great heights. At night the saturated air deposits 
droplets on the myriad leaves of the ridge forests. 

The gentle foothill country of area (C), brilliantly 
analysed for water conservation by Yeomans' 51 , 
supports the most viable agricultures, if the forest 
above is left uncut. Here, the high run-off can be led to 
midslope storage dams at the "Keypoint" indicated in 
Figure 3.11 (examined in much more detail in 
Yeomans' books). Using the high slopes as a watershed, 
and a series of diversion catchment drains and dams, 
water is conserved at the keypoints for later frugal use 
in fields and buildings. The water is passed with its 
nutrients to low dams, and released as clean water 
from the site. (This is the ideal: the reality often falls far 
short of it.) The lower slopes—those safe to use tractors 
on at least—can be converted to immense soil-water 
storage systems in a very short time (a single summer 
often suffices). This is a matter of soil conditioning, 
afforestation, water interception, or a combination of 

The plains of area (D) are the most open to wind 
erosion and the most resistant to water erosion. How¬ 
ever, it is here that great damage can occur by salting. 
Red and dusty rains and plagues of locusts are a result 
of the delinquent use of the plough, heavy machinery, 
and clean tillage of these flattish lands, together w-ith 
the removal of trees and hedgerows, and the 
conversion of the plains to monocultures of extensive 
grazing and grain cropping. 

It is on the plains areas that water is most cheaply 
stored, in soil and in large surface dams, where 
no-tillage crops, copses and hedgerows are 
desperately needed. This is where broadscale 
revolutions in technique can be implemented to 
improve soil health, reduce wind and water losses, and 
produce healthy foods. 

The forests on the high slopes, coupled with the 
thermal belt IGeiger"*'] of the house site make a 

P*0±T po«gT 



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lcou> NifiKTAiK 

1 PPM- 

MJP *oic.*TAB<L{ty 

NltfWT woe*J4A1osJ Of t*Mf 


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Co MV ex 

FIGURE 3.11 

Slope analysis and site planning in relation to aspect largely decide 



laL ow *5U)pGS A *77>6L£ 
WMTE SL *7t*AG£.; FlgU>S. 

Com cave. 

the placement of access, water supply, forests, and cropland Here 
we supply such analysis to a cool, humid region. 


remarkable difference to midslope climate and soil 
temperatures. Anyone who doubts this should walk 
towards an uphill forest on a frosty night, and measure 
or experience the warm down-draught from high 
forests. If these are above Zones 1 and 2, they present 
little or no fire danger. Their other functions of erosion 
control and water retention are well attested. 

Downslope, reflection from dams adds to the 
warmth. Solar collectors placed here transmit heat, as 
air or water circulating by thermosiphoning alone, and 
assist house, glasshouse or garden to function more 
efficiently. Even very slight slopes of 1:150 function to 
collect water and heat if well used in the design. 

The easy, rounded ridges of non-eroded lower slopes 
and their foothill pediments are a prime site for 
settlement. They allow filtration of wastes, inseparable 
from large populations, through lowland forest and 
lake, and the conversion of these wastes into useful 
timber, trees, fruits, and aquatic life. 

If zone and sector are imposed in plan, sun angle and 
landscape slope are assessed in elevation. These 
determine the following placements: 

SUN ANGLE describes the arc of the sun during 
summer and winter months, and so decides eave and 
sill placement of windows, areas of shade, and 
reflection or absorption angles of surfaces. Also, in 
every situation (even hot deserts), some part of the 
system should be left open to the sun for its energy 

ASPECT describes the orientation of the slope. A 
slope facing the sun will receive considerably more 
direct solar radiation than a slope facing the shade side 
(south in the southern hemisphere, north in the 
northern). The shaded side of hills may delay thaw and 
thus moderate frost effects in vegetation. In 
mid-latitudes, we seek the sunny aspect of slopes to 
achieve maximum sunlight absorption for our 
settlements and gardens. 

The final act in site planning is to orient all buldings 
and structures or constructs correctly, to face mid- sky, 
the sun, or the wind systems they refer to, or to shelter 
them from detrimental factors e.g. cold winter winds 
or late afternoon sun. 

In summary, if the elements of the design are 
carefully zoned, the sectors well analysed, the sun 
angle and slope benefits maximised for use, and the 
constructed environment oriented to function, then a 
better ground design results than most that now exist. 
As I reassure all would-be permaculture designers, 
you can do no worse than those prior designs you see 
about you, and by following the essentially simple 
outline above, you may well do much better. 
Incredible as it seems, these essential factors are the 
most frequently overlooked or ignored by designers to 
the present day, and retrofit is then the only remedy 
for ineffective design. 

_3 1 10_ 


In this book, I am concentrating on people and their 
place in nature. Not to do so is to ignore the most 
destructive influence on all ecologies: the unthinking 
appetite of people—appetite for energy, newspaper, 
wrappings, "art", and "recreation". We can think of our 
zones in other than product terms and management, as 
a gradation between an ecosystem (the home garden) 
managed primarily for people, and the wilderness, 
where all things have their right to exist, and we are 
only supplicants or visitors. Only excessive energy 
(human or fuel) enables us to assert dominance over 
distant resources. When we speak of dominance, we 
really mean destruction. 

What is proposed herein is that we have no right, nor 
any ethical justification, for clearing land or using 
wilderness while we tread over lawns, create erosion, 
and use land inefficiently. Our responsibility is to put 
our house in order. Should we do so, there will never be 
any need to destroy wilderness. Indeed, most farmers 
can become stewards of forest and wildlife, as they will 
have to become in any downturn in the energy 
economy. Unethical energy use is what is destroying 
distant resources for short-term use. 

Our zones, then, represent zones of destruction, 
information, available energy, and human dependency. 
The ■ ecologist" with large lawns, or no food garden, is 
as hypocritical as the "environmentalist" drinking from 
from an aluminium beer can and buying newspapers 
to read of destructive exploits. Both occupations 
exploit wilderness and people. 

In Zone 1 we are information developers; we tend 
species selected by, and dependent on, mankind. All 
animal species tend their "home gardens", and an 
interdependency arises that is not greatly different 
from the parasite-prey dependency. 

In Zone 2. already nature is making our situation 
more complex, and we start to learn from species other 
than our people-dependent selections. As we progress 
outwards, we can lose our person-orientation and gain 
real understanding of the necessity for all life forms, as 
we do not "need" to exploit most species. We in fact 
need and use only a few species of the hundreds of 
thousands that exist. 

In wilderness, we are visitors or strangers. We have 
neither need nor right to interfere or dominate. We 
should not settle there, and thus leave wastelands at 
our back. In wilderness we may learn lessons basic to 
good design, but we cannot improve on the 
information already available there. In wilderness, we 
learn of our little part in the scheme of all things. 


1. Everything is of use. It is not necessarily needed by 
people, but it is needed by the life complex of which we 
are a dependent part. 

2. We cannot order complex functions. They must 


evolve of themselves. 

3. We cannot know a fraction of what exists. We will 
always be a minor part of the total information system. 

Thus, we are teachers only in our home gardens, and 
learners elsewhere. Nowhere do we create. Everything 
we depend on we have evolved from what is already 
created, and that includes ourselves. Thoughtful people 
(those who get recreation from trying to understand) 
need wilderness as schools need teachers. Should we 
lose the wilderness, or suffer it to be destroyed, we will 
be recycled for more appropriate life in any number of 
ways, some very painful and protracted. We can also 
state our first "error" thesis here; such errors, once 
made, lead us into increasing problems. 


When we settle into wilderness, we are in conflict with 
so many life forms that we have to destroy them to 
exist. Keep out of the bush. It is already in good order. 



Almost all engineering design is based on small 
changes to existing designs, until some ultimate limit 
in efficiency or performance is reached. The whole 
process can take centuries, and the end result can be 
mass-produced if necessary. Kevin Lynch (1982) in 
his book Site Planning writes of site designing by 
incremental adaptation of already-existing designs: 
design by following physical systems that have been 
shown to work. He believes the best site planning of 
the past to be a result of this process, and that it in fact 
works very well unless some external and important 
condition (e.g. market or land ownership) changes. He 
maintains that this fine-tuning of successful design for 
a specific climate and purpose can be totally 
inappropriate if transferred out of culture, climate, or if 
applied to a different purpose. 

It is, however, the most successful way to proceed 
after selective placement and energy conservation is 
paid sufficient attention. Known effective design units 
and specifications, whether of roads, culverts, houses, 
garden beds, or technologies have been subjected to 
long tests, and have evolved from trials (or prototypes) 
to working and reliable standards. Even if 
"old-fashioned" (like overshot water wheels), they may 
yet represent a simplicity and an efficiency hard to beat 
without a considerable increase in expense and 

Such continual adaptation is the basis of feedback in 
systems undergoing establishment, where we make 
additions or changes to houses or plant systems. It is 
not the way, however, to satisfy the demands of a 
complex system which (like a private home and 
garden) has to satisfy a complex set of priorities. Nor 
does it cope with changing futures, new information 

and sets of values, or simply self-reliance and 



To sum up, in whole farm planning and in report 
writing, outlining areas of like soil, slope, or drainage 
will suggest sensible crops, treatments, fencelines and 
land use generally. If we accept what is there, ethical 
land use dictates conservative and appropriate usage. 
But (as may happen) if someone is determined to raise 
wheat on all that land regardless of variations, they can 
probably do so only if they command enough energy 
or resources. I am sure we can grow bananas in 
Antarctica if we are prepared to spend enough money, 
or can persuade penguins to heat a glasshouse! 

Insofar as we enter into village design, we may have 
financial and space constraints on upper or lower sizes: 
a "break-even" point and an "optimum" number of 
houses per unit area. However, if we neglect a foray 
into the social effects of settlement size and into the 
needful local functions related to settlement size, we 
may be designing for human misery, the under¬ 
servicing of needs, and even for such sociopathologies 
as riot and crime. Such designs may be economic (in 
cash terms), efficient for one use only, and totally 
inhuman. But they are built even,’ day. For example, it 
was found that rats subjected to breathing in the same 
airstream of their fellows experienced severe 
instability, physiological stress, and consequent 
pathologies akin to crowding stress. This is called the 
"Bruce effect" after the experimenter w-ho discovered it, 
and this effect may apply equally well to people. Yet in 
almost all cities, one can see people crammed into 
16-40 storey office buildings with no opening windows 
and only a single airstream! 

Site designing needs not a specialist approach, but 
rather a multi-disciplinary and bio-social approach 
that takes into account the effects the environment has 
on its intended occupants. 

Perhaps if we assembled all our considerable, 
diverse, and effective knowledge of both the parts and 
the whole order of design into a type of computer 
search or game-playing programme, we might ad¬ 
vance the whole design process as a realm of 
continuing and additive human knowledge, available 
to everyone. Such programmes could deal with a great 
deal of the fussy detail that now slows design—from 
plant list specifications to home construction 
details—leaving the designer with those 
imponderables about the processes observed on the 
land, the likely trends of future societies, future needs, 
and a measure of human satisfaction. 

In elaborating just some of the basic approaches to 
design, without including specialist solutions, I want to 
stress that all the approaches outlined are not only 
useful, but necessary. Only by some sensible 


combination of all the methods given can one select 
and assess all the elements that enter into a total design 
assembly, and so evolve a design that includes a large 
degree of self-management, takes account of details on 
site, suits the ethics and resources of people, locates 
ground features in an integrated way, and provides for 
natural systems and access routes to be properly 

_3 I 13_ 


The methodologies of polyculture design rely more on 
species interaction than on configuration, although 
both are necessary inputs to a design. Thus, in de¬ 
signing for best (or most beneficial) species assemblies, 
we need to know about, and use, the concepts of 
species guilds and the co-actions of species. 

In the natural world, we may often notice assemblies 
of plants or animals of different species that never- 

TABLE 3.4 



A perceived social problem. 


Values of energy conservation, self-reliance, 
and harmonious human occupancy.' 


Consideration of long-term biosocial factors. 

Research and consultation with clients, or 
assisting people to gain an education in design.* 


Allowing space, finance, and feedback to adjust 
activity, and allowing for new or overlooked needs' 

as they occur. 


A dynamic and healthy area inhabited by people 
with the power and understanding to make 
necessary changes. 



A drive to erect monuments or make money. 

Economic (as cash) considerations 
and the desire for profit. 


Purely functional values for short-term 
cost and material factors. 


External funding, little consultation, 
little client/people education. 


Selling off and not taking responsibility for 
the results. 



A dislocated populatio, powerless to effect change 
easily. Hence, dependency and anxiety. 





theless occur together over their range. Closer 
examination of such mixed assemblies often reveals a 
set of mutual benefits that arise from such convivial 
togetherness. These benefits offer help or protection to 
the whole assembly (as when one bird species acts as 
"lookout" for another, or defends others from hawks). 
When we design plant guilds, as we always try to do in 
a polyculture, we try to maximise the benefits of each 
species to the others. We can also add factors of 
convenience to ourselves, or which save us inputs of 
fertiliser or pesticides, as in the "apple-centred" guild 
described below. 

A guild, then, is an harmonious assembly of species 
clustered around a central element (plant or animal). 
This assembly acts in relation to the element to assist 
its health, aid our work in management, or buffer 
adverse environmental effects (see Figure 3.12). Let us 
list some of the reasons to place species in association: 

To_benefit as selected species by: 

• Reducing root competition from (e.g.) invasive 
grasses. Almost all our cultivated food trees thrive in 
herbal ground covers, not grasses. 

• Assisting pest control in various ways: 

— by providing anti-feedants (bitter or 
unpalatable browse or chemical deterrents), e.g. 
nasturtium roots provide root chemicals to tomatoes 
or gooseberries which deter whitefly. Many plants, 
fermented or in aqueous extraction, deter pests or act 
as anti-feedants when sprayed on leaves of the 
species we wish to protect. 

— by killing root parasites or predators, e.g. 
Crotalaria captures nematodes that damage citrus 
and solanaceous roots; Tagetes marigolds "fumigate" 
soils against grasses and nematodes. 

— by hosting predators, as almost all 
small-flowered plants |especiallyQui7/a/fl, many 
Acacia species, tamarisk, Compositae (the daisy 
family) and UmMliferae such as dill, fennel, carrot, 
and coriander! host robber-flies and predatory 

• Creating open soil surface conditions, or 
providing mulch. For example, comfrey and globe 
artichokes allow- tree roots to feed at the surface 
(unlike grasses, which competes with tree roots), while 
spring bulbs (daffodils) or winter-grown wild Allium 
species, whose tops die down in mid-spring do not 
compete with deciduous tree roots in summer dry 
periods, nor do they intercept light rains. 

• Providing free nutrients: w-oody or herbaceous 
legumes fix nitrogen or other essential nutrients via 
root associates, stimulate soil bacteria or fungi, and 
benefit associated trees. Clovers; trees such as Acacia. 
Casuarina. and Pultenaea ; sugar-providing grasses 
(sugar cane); and high humus producers (bananas) all 
assist orchard species. Many can be slashed or 
trimmed to give rich mulch below trees or between 
crop rows. 

• Providing physical shelter from frost, sunburn, or 

the drying effects of wind. Many hardy windbreak 
species of equal or greater height, both as edge 
windbreak or in-crop crown cover exclude frost, 
nullify salty or hot winds, provide mulch, and 
moderate the environment towards protecting our 
selected species. Examples are borders of bamboo, 
cane grasses, Casuarina, hardy palms, and tamarisks. 
In-crop shade shelter of legumes are needed by such 
crops as avocado, citrus, and cocoa or coffee (or any 
crops needing partial shade). In-crop trees can 
eliminate frost effects in marginal frost areas. 

To assist us in gathering : 

• Culinary associates: it is of some small benefit in 
detailed planning to keep common culinary associates 
together (tomatoes with parsley and basil; potatoes 
with a tub of mint) so that we also gather them 
together for cooking, salads, or processing (dill with 
cucumbers). Thus we reduce work. Dill and apples also 
go well together, raw or cooked, and dill is one of the 
Umbelliferae that host predatory wasps below apple 

SBfiqfic animal.associate? pf a gyild: 

We have made reference, in pest control, to host plants. 
These can be best specified by observing, researching, 
or selecing plants to host quite specific predatory 
wasps, lacewings, or ladybirds. Vertebrates that assist 
our selected crop species are: 

• Ground foragers, e.g. pigs or poultry specifically 
used to clear up the fallen fruit that host fruit fly or 
larval forms of pests. Foragers can be run in orchards 
for that relatively short period of the year when fruit is 
falling and rotting, or they can be used to eat reject 
fruit and deposit manures. 

• Insectivores: birds, in particular, that search bark 
crevices (woodpeckers, honey-eaters) for resting larvae 
and egg masses. To encourage these, plant a very few 
scattered flowering shrubs and herbaceous plants such 
as Kniphofia. Banksia, Salvia. Buddleia, and Fuschia. All 
of these provide insect and nectar foods for 
insectivorous birds. 

• Mollusc control: snails and slugs are almost totally 
controlled by a duck flock on range, and several large 
lizards (Tiliqua spp.) also feed primarily on snails. 
Ducks can be ranged seasonally (autumn to spring) in 
plant systems, and in summer on marshlands. Ducks 
will eat seedlings, so that appropriate scheduling is 

• Guard dogs: for deer, rabbits, and other vertebrate 
pests. A small number of guard dogs, fed and 
kennelled in orchards, are sufficient control for fox 
predation on orchard poultry foragers. Such dogs, 
reared with domestic poultry, do not attack the flocks 

• Hawk kites suspended over a berry crop, or flown 
as light model planes over an extensive grain crop 
deter all flock-bird predators of the crop, and are more 
dependable than natural hawks. They need to be 
removed when not needed, so that birds do not get 






A (X 7 A 




accustomed to them. 

These are just part of the total guilds. Ever)' designer, 
and every gardener, can plan such guilds for specific 
target species, specific pests and weed control, and 
specific garden beds or orchards. 


A guild of plants and animals is defined here as a 
species assembly that provides many benefits for 
resource production and self-management (more 
yields, but lower inputs). In general, the interactions 
between plant and animal species are thus: 

• Most species get along fine; this is obvious from a 
study of any complex home garden or botanical 
garden; perhaps 80% of all plant species can co- mingle 
without ill effect. 

• Some species greatly assist others in one or other 
of many ways. Positive benefits arise from placing such 
species together where they can interact (10-15% of all 

• A minority of species show antagonistic be¬ 
haviour towards one or more other species. This in 
itself can be a benefit (as in the case of biological pest 
control) or a nuisance (as in the case of rampancy or 
persistent weeds or pests). Perhaps as few as 5% of all 
species act in this way. 

Now, to give the above classes of interaction a more 
useful analytic structure, we will allot symbols, as 

+ : this is used to indicate a beneficial result of 
interaction, with a yield above that of some base 
level (judged from a monoculture or control crop of 
the species). 

o : this is used to indicate “no change " as a result of 
interaction, on the same basis. 

-: this is used to indicate a reduction in yield or vigour 
as a result of interaction with another species. 

Thus, for two useful species (each selected for a use¬ 
ful product), we have the simple tabulation of Table 
3.5, which gives us all possible interactions. 

The array is such that only three interactions benefit 
us, three are neutral, and three are antagonistic in effect 
effect. By grouping scores, we can analyse for 
beneficial effects in our interaction table, and act on 
these. However, because of the vagaries of weather in 
any given year, many times a peasant farmer may 
accept a (- +) effect just to ensure that he at least gets a 
crop, even if it is of the "losing" species. It is always 
safer to mix or complicate crop than to pin hopes on a 
single main crop. In fact, be guided by analyses but 
study reality! 


In common usage, COACTION implies a force at work: 

one that restrains, impedes, compels, or even coerces 
another object. INTERACTION implies reciprocal 
action: two things acting on each other. This is an 
important distinction. A final category is INACTION, 
or an absence of any detectable action. 

We cannot at this point guess which state applies, but 
when we put two species together, there are these 

• One acts on the other (co-action or unilateral 

• Both act on each other (interaction or mutual 
action); and 

• Neither act (inaction or neutrality). 

TABLE 3.5 




















It would seem probable that in the case of (++) and (- 
-) we have mutual action or interaction. In the case of 
(-o), (o—), (+o), (o+), (♦-), (-+) one only needs to be 
acting, a form of co-action. In the case of (oo) neither 
acts, no effects appear, and both are inactive insofar as 
our measures can detect. 

We need to observe and perhaps analyse each case, 
but it does seem probable that such states of action 
apply. Some such states can be named and examples 
given, for instance: 

A. Mutual Ac tion S ta tes 

++ This is called symbiosis, and is common both in 
nature and in society. It is a "win-win” situation 
ideally suited to guild development. An example is 
the mycorrhizal associates of higher plants, where 
mutualism or fair trade occurs between a plant and its 
root associate. 

- Haskell (1970) has coined the word synnecrosis 
(The Science Teacher 37(9) Supplement), and it is 
obviously uncommon. War is our best example of a 
’lose-lose’ situation, but there are also battles between 
plants for light, nutrients, and space. There are forms 
of chemical warfare in both plants and animals. 


B Single Action States 

-o Haskell calls this amensalism. It hurts the actor, 
not the other. A butterfly attacking a rhinocerous 
would fit, or a wasp parasite "glued" to a tree it attacks, 
as is the case with some pine trees and Sirex wasps. 

o- Called allolimy by Haskell, it leaves the actor 
unaffected but hurts the other, e.g. a walnut tree beside 
an apple tree yields well, but the juglones secreted by 
its roots act to kill or weaken the apple. In the same 
way grasses act to weaken most deciduous fruit trees. 

♦o Termed commensalism. Even though the actor 
benefits, the other remains unaffected, e.g. an epiphyte 
attached to a sturdy tree, such as vanilla on a coconut 

o+ Called allotrophy by Haskell. The actor is 
unaffected, the other benefits. Examples are a teacher 
and student relationship, or a charity where one hands 
on surplus goods to another person less fortunate. 

♦- Called parasitism, the actor benefits, the other 
loses if the actor is the parasite. All pathogens and 
parasites tend to weaken or take from the host. 

-+ Self-sacrifice. The actor loses. This is the reverse 
of parasitism, and a better word might be 
self-deprivation to help others. This is often seen in 
nature, mostly as individuals helping members of the 
same family or species. Medals are awarded for this in 
human society, and we call it selflessness or even 

oo Neither one acts. No one is hurt, no one wins. 
Neutrality pacts may achieve this result in society, or 
we observe it commonly in nature. There are critical 
areas in nature (water holes, salt licks, grooming 
stations) where antagonistic species agree on neutrality. 
In fact, many plant species appear to be basically 
neutral in behaviour. 

Such analyses suit two-species interactions, but 
where we depart (in the designed system) from nature 



SPECIES A (a palm) 
















In order of benefit (increase in palms, less increase or 
decrease in lantana): 

(- , +)>(o'+)>(-'o)>(+ , *)>(o'o)>(--)>( -)>(o’-)>(*'o) 
Best result.>Neutral.>Worst result. 

is that we may value (in the sense of obtaining a yield 
from) only one of these species. Let this be species A in 
Table 3.6. The other can be a weed or a species such as 
Lantana, which we might wish to eliminate. In this 
case, we can set up a matrix as diagrammed in Table 

This is a very necessary type of analysis for selecting 
useful plants that will eliminate or weaken an 
unwanted weed species. All such analyses can be made 
using plant/plant, animal/animal, or plant/ animal 

How do we observe co-action? This is quite simple in 
the field, providing there are plenty of examples to 
score, and we have set some criteria to score by. For 
example, take a town or area with a great many trees 
planted in the backyards. Select any one of these 
species for criteria, say an apple, then decide on how to 
score, e.g. (in compounds with apples and other 
species of plants growing): 

+: apple tree healthy, bearing very well, not stunted or 

o: apple tree healthy, in fair order, bearing. 

apple tree bearing poorly, sick or dying, 
x: no apple tree in this yard. 

TABLE 3.7 



Other trees near, 
or in, yard. 


















Scoring can be of specific pairings: 


















Then, we draw up a co-action matrix on a piece of 
paper, with the “apple” score at the top and "other 
trees’ down the left side (Table 3.7). Tally the scores by 
walking from yard to yard. 

We quickly see that where there are walnuts, apples 
are sick or absent (o-). However, healthy apple trees 
coexist with both mulberries and Acacias (+o) and (oo). 
Ideally, we use a similar score for each species of other 
tree, so that our co-action results score the same 
criteria for walnut, mulberry, and Acacia that we score 
for apple. 

Additional field notes are useful. Healthy, untended 
apple trees often have quite a specific understory of 
spring bulbs, comfrey, clover, iris, nasturtium, etc. This 
too should be noted as we go. I have, in fact, carried 
out such analyses, and some of the results will be used 
as a real example in the next section. 


If we wish to construct a guild, then we need to bring 
two or more species into close proximity where we can 
judge the effects of one on the other. If we have a () 
result anywhere, we might be able to intervene with a 
third or fourth party which we can call an arbitrator, a 
buffer, or an intervenor. 

• Apple next to walnut produces (-o): not desirable; 
the apple sickens or dies. 

• Apple next to mulberry produces (+o): a good 

• Mulberry next to walnut produces (oo): mutual 

Thus, apple then mulberry then walnut gives us 
(+oo). By this intervention strategy, we have, in effect, 
cancelled out the (—) and have a nett benefit in a three- 
three-species array. That is, we can use several 
two-species results to achieve a better result with three 
species, which goes beyond accepting (fatalistically) 
the primary conflict. Here, a mulberry is the intervenor 
or critical species or element in conflict resolution. We 
can take this further again by examining yet other 

• Acacia next to walnut gives <o+) 

• Acacia next to mulberry gives (o+) 

Now, apple-mulberry-Acacifl-walnut gives us (++o+), 
which is much better again. So we proceed to isolating 
and arranging guilds to maximise benefits and 
eliminate conflicts. This is part of the skill of planning 
strip or zone placements of mixed species. 

Here, we have to consider placement of interactive 
elements. Obviously, there is a commonsense close 
spacing for many plants and machine components, but 
as the distance between living components widens, we 
can never be quite sure that chemical or behavioural 
interaction ceases. Consider the case of two territorial 

birds, displaying or calling a mile or more apart. To us, 
they appear as individuals; to each bird, the other is in 
clear interaction. There is distant interaction, too, via 
pollen or spores in plants, and perhaps even by 
gaseous or chemical "messengers”. This is certainly 
true of some mammals, so that effects of one on the 
other can be passed on by a sense of smell, even 
though they are not nearby at that time, e.g. urine 
marking territory. The great whales may well be 
communicating by sound around the whole globe. 

Configuration in planning a guild with intervening 
species between hostile 0 species, comes in assessing 
the distance across the interaction boundary that the 
effect takes place, and in then arranging the guild 
species to obtain a maximum of (++), (o+), or (+o) 
effects. For example, we find a (++) condition with 
legume/grain or fruit-tree/tree legume interplants. We 
know that the effect, for grains, extends from 1.5-2 m 
into the crop; thus for a configurational design, we can 
spiral or strip-plant these two species for a total 
positive edge interaction effect in crop. Such careful guild 
analyses and configurations are the basis of species 
planning in permaculture. 

For more critical geometric analyses, see such texts as 
Rolfe A. Leary’s Interaction Geometry: An Ecological 
Perspective , USDA Forest Service, General Technical 
Report NC-22,1976. This text has a useful reference list 
and is issued by the North Central Forest Experimental 
Station, Fulwell Ave, St. Paul, MN, 55108, USA. 



Nature shows us that a sequence of processes arise in the 
establishment of "new" systems on such devastated 
landscapes as basalt flows and ice-planed or 
flood-swept sites. The first living components are 
hardy pioneer species, which establish on these damaged 
or impoverished environments. Thus we see "weeds" 
(thistles, Lantana) occupying overgrazed, eroded, or 
fired areas. These pioneer species assist the area by 
stabilising water flow in the landscape, and later they 
give shelter, provide mulch, or improve soil quality for 
their successors (the longer-term forest or tree crop 

To enable a cultivated system to evolve towards a 
long-term stable state, we can construct a system of 
mixed tree, shrub, and vegetable crop, utilising live¬ 
stock to act as foragers, and carefully planning the 
succession of plants and animals so that we receive 
short-, medium-, and long-term benefits. For example, 
a forest will yield first coppice, then pole timbers, and 
eventually honey, fruit, nuts, bark, and plank timber as 
it evolves from a pioneer and young, or crowded, 
plantation to a well-spaced mature stand over a period 
of 15-50 years. 

Unlike the processes of nature, however, we can 


place most of the elements of such a succession in one 
planting, so that the pioneers, ground covers, 
under-story species, tree legumes, herbage crop, mulch 
species, the long-term windbreak and the tree crop are 
all set out at once. So many species and individuals of 
each species are needed to do this that it is usually 
necessary to first create a small plant nursery to supply 
the 4,000-8,000 plants that can be placed on a hectare. 
While these are growing in their pots, we can fence and 
prepare the soil, and then plant them out to a 
carefully-designed long-term plan. 

Where this approach is used, as it has been by many 
permaculturalists on their properties, quite remark¬ 
able changes occur over two to three years. Mulch is 
produced on site for the long-term crop, while weed 
competition, wind, and frost effects are nullified or 
moderated. Cropping can be continuous as the annuals 
or herbaceous perennials effectively control unwanted 
grasses and weed species. For instance, radish or 
turnip planted with tree seedlings control grasses until 
the small tree provides its own grass control by 
shading. Figure 3.13 gives an indication of how a 
system can accept different species of plants and of 
animal browsers as it evolves. 



Every design is an assembly of components. The first 
priority is to locate and cost those components. Where 
our resources are few, we look closely at the site itself, 
thinking of everything as a potential resource (clay, 
rock, weeds, animals, insects). We can think of labour, 
skill, time, cash, and site resources as our inter¬ 
changeable energies: what we lack in one we can make 
up for by exchange for another (e.g. clothes-making in 
exchange for roof tiles). The best source of seed and 
plants is always neighbours, public nurseries, or 
forestry departments. From the early planning stages, 
it pays to collect seed, pots, and hardy cuttings for the 
site, just as it pays to forage for second-hand bricks, 
wood, and roofing. 

The planning stage is critical. As we draw up plans, 
we need to take the evolution in stages, to break up the 
job into easily-achieved parts, and to place com¬ 
ponents in these parts that will be needed early in 
development (access ways, shelter, plant nursery, water 
supply, perhaps an energy source). Thus, we design, 
assess resources, locate components, decide priorities, 
and place critical systems. Because impulsive 
sidetracks are usually expensive, it is best to fully plan 
the site and its development, changing plans and 
designs only if the site and subsequent information 
forces us to do so. 

On a rural (and sometimes urban) site, FENCING or 
hedgerow, SOIL REHABILITATION by mulch (or 
loosening by tools), FROSION CONTROL, and 

WATER SUPPLY are the essential precursors to 
successful plant establishment, for we can waste time 
and money putting out scattered plants in compacted, 
impractical, and dry sites. Any soil shaping for roads, 
dams, swales, terraces, or paths needs to be finalised 
before planting commences. 

For priority in location, we need to first attend to 
Zone 1 and Zone 2; these support the household and 
save the most expense. What is perhaps of greatest 
importance, and cannot be too highly stressed, is the 
need to develop very compact systems. In the Philip¬ 
pines, people are encouraged to plant 4m 2 of 
vegetables—a tiny plot—and from this garden they get 
40-60% of their food! We can all make a very good four 
metres square garden, where we may fail to do so in 40 
square metres. 

Similarly, we plant and care for ten critical trees (for 
oils, citrus, nuts, and storable fruit). We can take good 
care of these, whereas if we plant one hundred or one 
thousand, we can lose up to 60 % of the trees from lack 
of site preparation and care. Thus, ten trees and four 
metres square , well protected, manured, and watered, 
will start the Zone 1 system. 

Starting with a nucleus and expanding outwards is 
the most successful, morale-building, and easily- 
achieved way to proceed. Broadscale systems have 
broadscale losses and inefficiencies. As I have made 
every possible mistake in my long life, the advice 
above is based on real-life experience. To sum up: 

• Design the site thoroughly on paper. 

• Set priorities based on economic reality. 

• Locate and trade for components locally or 

• Develop a nucleus completely. 

• Expand on information and area using species 
proved to be suited to site. 

Precisely the same sort of planning (nucleus 
development) applies to any system of erosion control, 
rehabilitation of wildlife or plants, writing books, and 
creating nations. Break up the job into small, easily 
achieved, basic stages and complete these one at a 
time. Never draw up long lists of tasks, just the next 
stage. It is only in the design phase that we plan the 
system as a whole, so that our smaller nucleus plans 
are always in relation to a larger plan. 

Instead of leaping towards some imaginary end 
point, we need to prepare the groundwork, to make 
modest trials, and to evolve from small beginnings. A 
process of constant transition from the present to the 
future state is an inevitable process, modest in its local 
effect and impressive only if widespread. Thus, we 
seek first to gain a foothoid, next to stabilise a small 
area, then to develop self-reliance, and only after this is 
achieved to look for exportable yields or commercial 

Even in a commercial planting it is wise to restrict the 
total commercial species to 3-10 reliable plants and 
trees, so that easier harvesting and marketing is 
achievable, although the home garden and orchard can 
maintain far greater diversity of from 25-75 species or 




I mm 




Thus, our design methodologies seek to take into 
account all known intervening factors. But in the end it 
comes down to flexibility in management, to steering a 
path based on the results of trials, to acting on new 
information, and to continuing to observe and to be 
open or non-discriminatory in our techniques. 

The success of any design comes down to how it is 
accepted and implemented by the people on the 
ground, and this factor alone explains why grand 
centralised schemes more often result in ruins and 
monuments than in stable, occupied, and well- 
maintained ecologies. 

We can design any expensive, uncomfortable, or 
ruinous system as long as we do not have to live in it, 
or fund it ourselves. Responsible design arises from 
recommending to others the way you have found it 
possible to work or to live in a similar situation. It is 
much more effective to educate people to plan for 
themselves than to pay for a permanent and expensive 
corps of "planners” who lead lives unrelated to those 
conditions or people for whom they are employed to 

_ 3A6 _ 


Except for the complex subject of village design, a 
property design from one-fourth to 50 ha needs firstly 
a clear assessment of "client or occupier needs", and 
stated aims or ideas from all potential occupiers 
(including children). A clear idea of the financial and 
skill resources of occupants is necessary so that the 
plan can be financially viable. 

With a base map, aerial photograph, or a person as a 
guide, the designer can proceed to observe the site, 
making notes and selecting places for: 

• Access ways and other earthworks; 

• Housing and buildings; 

• Water supply and purification, irrigation; 

• Energy systems; and 

• Specific forest, crop, and animal system 

All the above are in relation to slope, soil suitability 
and existing landforms. By inspection, some priorities 
may be obvious (fire control, access, erosion 
prevention). Other factors need to be tackled in stages 
as time, money, and species permit. At the end of each 
stage, trial, or project, both past performance and 
future stage evolution should be assessed, so that a 
guide to future adjustments, additions, or extension is 
assembled as a process. In all of this, design 
methodologies plus management is involved, and it is 
therefore far better to train an owner-designer who can 
apply long-term residential management than to 
evolve a roving designer, except as an aide to initial 

placements, procedures, and resource listings. 

The restrictions on site use must first be ascertained 
before a plan is prepared or approved. In the matter of 
buildings, easements, health and sewage requirements, 
permits, and access there will probably be a local 
authority to consult. If water (stream) diversions are 
foreseen, state or federal authorities may need to be 

The homely, but probably essential process of 
building up real friendship between residents, 
designers, officials, and neighbours should be a 
conscious part of new initiatives. Small local seminars 
help a lot, as district skills and resources can be 
assessed. There is no better guide to plant selection 
than to note district successes, or native species and 
exotics that usually accompany a recommended plant. 
Nearby towns, in gardens and parks, often reveal a rich 
plant resource. 

As every situation is unique, the skill of design (and 
often of market success) is to select a few unique 
aspects for every design. These can vary from unique 
combinations of energy systems, sometimes with 
surplus for sale, to social income from recreational or 
accommodation uses of the property. This unique 
aspect may lie in special conditions of existing 
buildings, vegetation, soil type, or in the social and 
market contact of the region. Wherever occupants have 
special skills, a good design can use these to good 
effect, e.g. a good chemist can process plant oils easily. 

A design is a marriage of landscape, people, and 
skills in the context of a regional society. If a design 
ended at the physical and human aspects, it would be 
still incomplete. Careful financial and legal advice, plus 
an introduction to resources in these areas, and a clear 
idea for marketing or income from services and 
products (with an eye to future trends) is also essential. 

Over a relatively short evolution of three to six years, 
a sound design might well achieve: 

• Reduction in the need to earn (conservation of 
food and energy costs). 

• Repair and conservation of degraded landscapes, 
buildings, soils, and species at risk. 

• Sustainable product in short-, medium-, and 

• A unique, preferably essential, service or product 
for the region. 

• Right livelihood (good work) for occupants in 
services or goods. 

• Sound and safe legal status for the occupiers. 

• An harmonious and productive landscape without 
wastes or poisons. 

• A cooperative and information-rich part of a 
regional society. 

These then, or factors allied to them, are the test of 
good design over the long term. For many regions, a 
designer or occupant can provide species (as nursery), 
resources (as education), services (as food processing 
or lease), or simply an example of sustainable future 
occupations. Pioneer designers in a region should seek 
to capitalise on that pioneer aspect, and provide 


resources for newcomers to the region. 



Definition of Permaculture Design: Permaculture 
design is a system of assembling conceptual, material, 
and strategic components in a pattern which functions 
to benefit life in all its forms. It seeks to provide a 
sustainable and secure place for living things on this 

Functional Design: Every component of a design 
should function in many ways. Every essential 
function should be supported by many components. 

Principle of Self-Regulation: The purpose of a 
functional and self-regulating design is to place 
elements or components in such a way that each serves 
the needs, and accepts the products, of other elements. 


Chapter 4 


The curve described by the earth as it turns is a 
spiral, and the pattern of its moving about the 
sun... The solar system itself being part of a 
spiral galaxy also describes a spiral in its move¬ 
ment... Even for the case of circular movement, 
when one adds in the passage of time, the total 
path is a spiral... The myriad things are con¬ 
stantly moving in a spiral pattern... and we live 
within that spiral movement. 

(Hiroshi Nakamura, from Spirulina: Food for a 

Hungry World, University of the Trees Press. P.O. 

Box 66, Boulder, California 95006, USA.) 

The patterns and forms of a tree are found in 
many natural and evolved structures: an ex¬ 
plosion. event, erosion sequence. Idea, germin¬ 
ation. or rupture at an edge or Interface of two 
systems or media (here, earth and atmosphere) 
may generate the tree form in time and space. 
Many threads spiral together at the point of 
deformation of the surface and again disperse. 
The tree form may be used as a general teaching 
model for geography, ecology, and evolution: it 
portrays the movement of energy and particles In 
time and space. Foetus and placenta: vertebrae 
and bones: vortices: mushrooms and trees: the 
Internal organs of man: the phenomena of vol¬ 
canic and atom bomb explosions: erosion 
patterns of waves, rivers, and glaciers: com¬ 
munication nets: Industrial location nets: 
migration: genealogy: and perhaps the universe 
itself are of the general tree form portrayed. 

Simple or multiple pathways describe yin- 
yang. swastika, infinity, and mandala symbols. A 
torus of contained forces evolves with the 
energies of the pattern, like the doughnut of 
smoke that encircles the pillar of the atomic 

(Bill Mollison, Permaculture One, 1978.) 

Everything the Power of the World does is done in 
a circle... The wind, in its greatest power, whirls... 
The life of a man Is a circle from childhood to 
childhood, and so Is everything where power 
moves. Our teepees were round like the nests of 
birds, and these were always set in a circle, the 
nation's hoop, a nest of many nests.... 

(Black Elk.) 

_ 4.1 _ 


It is with some trepidation that 1 attempt a treatise on 
patterns. Nevertheless, it must be attempted, for in 
patterning lies much of the ground skill and the future 
of design. Patterns are forms most people understand 
and remember. They are as memorable and repeatable 
as song, and of the same nature. Patterns are all about 
us: waves, sand dunes, volcanic landscapes, trees, 
blocks of buildings, even animal behaviour. If we are to 
reach an understanding of the basic, underlying 
patterns of natural phenomena, we will have evolved a 
powerful tool for design, and found a linking science 
applicable to many disciplines. For the final act of the 
designer, once components have been assembled, is to 
make a sensible pattern assembly of the whole. 
Appropriate patterning in the design process can assist 
the achievement of a sustainable yield from flows, 
growth forms, and timing or information flux. 

Patterning is the way we frame our designs, the 
template into which we fit the information, entities, 
and objects assembled from observation, map overlays, 
the analytic divination of connections, and the selec¬ 
tion of specific materials and technologies. It is this 
patterning that permits our elements to flow and 
function in beneficial relationships. The pattern is 
design, and design is the subject of permaculture. 


Beyond the rigour of the simple Euclidean regu¬ 
larities beloved of technologists and architects, there 
remains most (or all) of nature. Nature imperfectly 
round, never flat or square, linear only for infinitesimal 
distances, and stubbornly abnormal. Nature flowing, 
crawling, flying, weeping, and in apparent disarray. 
Nature beyond precise measurement, and 
comprehensible only as sensation and system. 

Nothing we can observe is regular, partly because we 
ourselves are imperfect observers. We tell fortunes (or 
lose them) on the writhing of entrails or cathode ray 
graphics, on the scatters of dice or bones, or on arrays 
of measures. Are the readings of tea leaves any less 
reliable than the projections of pollsters? Regular 
things are those few that are mechanical or shaped 
(temporarily) by our own restricted world view; they 
soon become irregular as time erodes them. Truth, like 
the world, changes in response to information. 

There are at least these worthwhile tasks to attempt: 

STANDING, both as attempts at forming more general 
pattern models, and as examples of natural 
phenomena that demonstrate such models. 

2. A LINKING DISCIPLINE that equally applies to 
geography, geology, music, art, astronomy, particle 
physics, economics, physiology, and technology. This 
linking discipline would apply to conscious design 
itself and to the information flow and transfer 
processes that underlie all our disciplines. Such a 
unifying concept has great relevance to education, at 
every level from primary to post-graduate disciplines. 

amples of how applied patterning achieves our desired 
ends in everyday life, where rote learning, linear 
thinking, or Euclidean geometry have all failed to aid 
us in formulating sustainable settle-ments. It is in the 
application of harmonic patterns that we demonstrate 
our comprehension of the meaning of nature and life. 

There have been many books on the subject of sym¬ 
bols, patterns, growth, form, deformation, and 
symmetry. The authors often abandon the exercise 
short of devising general models, or just as a satis¬ 
factory mathematical solution is evolved for one or 
more patterns, and almost always before attempting to 
create applied illustrations of how their efforts assist us 
in practical life affairs. Some are merely content to list 
examples, or to make catalogues of phenomena. Others 
pretend that meanings lie in pattern or number 
alone—that patterns are symbols of arcane knowledge, 
and they assert that only an unquestioned belief 
unlocks their powers. 

The simple pattern models figured herein are in¬ 
tended to be a useful adjunct to designers and 
educators. They also illustrate how we can portray our 
thinking about life, landscapes, and the communality 
that is nature. Learning a master pattern is very like 
learning a principle; it may be applicable over a wide 
range of phenomena, some complex and some simple. 
As an abstraction, it assists us to gain meaning from 
life and landscape and to comprehend allied 


One can spend endless hours seeking further 
scientific, mystical, or topological insights into pattern. 
The process is addictive, and I am as unwilling to 
abandon this chapter as 1 was to start it, but I trust that 
others, better equipped, will expand and further 
explain the basic concepts. I believe that it is in 
sophisticated pattern application that the future of 
design lies, and where many solutions to intractable 
problems may be found. 

We have a good grasp on the behaviours of pattern 
in natural phenomena if we can explain the SHAPES of 
things (in terms of their general pattern outlines); the 
networks and BRANCHING of tributaries (gathering 
flows) and distributaries (dispersal flows); the 
PULSING and flow regulation within organisms or the 
elements of wind, water, and magma; and illuminate 

Further, if WAVE phenomena and STREAMLINES 
are contained within our pattern analysis, as real 
waves or as time pulses, these and their refraction and 
interference patterns form another set of pattern 
generators, responsible for coasts, clouds, winds, and 
turbulent or streamlined flow. And, if we can show 
how the pattern outlines of landscapes, skeletal parts, 
or flow phenomena fit together as MATRICES 
(interlocking sets), or arise from such matrices (e.g. 
whirlwinds from thermal cells), then we can generate 
whole landscape systems or complete organisms from 
a mosaic of such patterns. 

In nature, events are ordered or spaced in discrete 
units. There are smaller and larger orders of events, 
and if we arrange like forms in their orders, we will find 
clusters of measures at certain sizes, volumes, lengths, 
or other dimensions. This is true for river branches, 
social castes, settlement size, marsupials of the same 
form, and arrays of dunes, planets, or galaxies. 

In the following pages, I will try to include all this 
and to derive it from the basis of a single "simple" 
model (Figure 4.1), which, understood in all its parts, 
has each of these phenomena, and a great many more 
subtle inferences, within it. Not all, or even many, of 
these shapes, symbols, symmetries, scatters, or forms 
will be individually described or figured here, but the 
basic pattern parts will be briefly described and related 
to each other. The basic model itself is derived from a 
stylised tree form. 

We should not confuse the comprehension of FORM 
with the knowledge of SUBSTANCE—"the map is not 
the territory"—but an understanding of form gives us a 
better comprehension of function, and suggests 
appropriate strategies for design. 

_ ±2 _ 


When we look about us in the world, we see the hills, 


rivers, trees, clouds, animals, and landforms generally 
as a set of shapes, apparently unrelated to each other, 
at least as far as a common underlying pattern is 
concerned. What do we see? We can list some of the 
visible forms as follows: 

• WAVES on water and "frozen' as ripples in dunes 
and sandstones, or fossilised quartzites and slates. 

• STREAMLINES, as foam strips on water, and in 
streams themselves. 

• CLOUD FORMS in travertine (porous calcite from 
hot springs), tree crowns, and "puffy" clouds or as 
cloud streams. 

• SPIRALS in galaxies, sunflowers, the global 
circulation of air, whirlpools, and chains of islands in 

• LOBES, as at the edge of reefs, in lichens, and 
fringing the borders of salt pans. 

• BRANCHES, in trees and streams converging or 
diverging; explosive shatter zones. 

• SCATTERS of algae, tree clumps in swamps, 
islands, and lichens on rocks. 

• NETS as cracks in mud, honeycomb, inside bird 
bones, in the columns of basalt (as viewed from above), 
and cells of rising and falling air on deserts. 

The NETS or cracks in mud and cooling lava are 
shrinkage patterns caused not by flow or growth, but 
by the lateral tension of drying or cooling, as are many 
patterns in iceflows and the cracked pattern of pottery, 
or the cracks in bark on trees. Thermal wind cells arise 
at the confluence of large heat cells on desert floors, 
forming a net pattern if viewed from above or below. 

In all of these categories, I hope to show- that one 
master pattern is applicable, and that even the bodies 
of animals are made up of bones, organs, and muscles 
of one or more of the forms above. 1 will link these 
phenomena—generated by growth and flow— into a 
single model form. That form is a stylised tree (Figure 
4.1). Around the central tree form of this model are 
arranged various cross-sections, plans, longitudinal 
sections, and streamline paths, all derived from real 
sections, paths, or projections of the tree. 

The evolution ot such a form from an initial point in 
space-time, 1 call an EVENT. Such events can be 
abstract or palpable. They have in common an origin 
(O), a phase of growth (T1-T6: an expression of their 
energy potential), decay, and dissolution into other 
events of a like or unlike form. The event of a tree is at 
least three-dimensional, and must be thought of as 
extending into and out of a plane (P). However, many 
similar events such as migration patterns or glaciation 
can be as well portrayed (as they are seen in aerial 
photographs) as two-dimensional. 

The curvilinear STREAMLINES (S1-S9), are seen to 
curve or spiral through the Origin, just as (in fact) the 
phloem (storage cells) and xylem (sapbearing cells) 
spiral through the X-X' axis, or earth surface plane (P), 
of a real tree. Not so easy to portray is the fact that the 
xylem is external to the stems and internal to the roots, 
and the phloem the reverse. At a zone in the plane <P), 

therefore, these cells INTERWEAVE or cross over as 
they spiral out of or into the media. 

This deceptively simple "apple core" or tree shape, 
spiralling out of the plane <P) is a slow-moving vortex 
such as we see in tornadoes and whirlpools. Traffic 
through the streamlines is in both directions. In trees, 
sugars and photosynthetic products travel from crown 
to root margin, and water and minerals from roots to 
crown. Thus, each margin of our pattern is both 
collecting and distributing materials from different 
media. The tree trades both ways with elements of the 
media, and there is an active water and gaseous 
exchange with the media (Ml, M2). Two-way trade is 
the normality of plants, organs, and natural forms. 

As we know, a crosscut of a tree stem, the basis of the 
study of dendrochronology, reveals a target pattern of 
expanding growth (by which the tree adds bulk 
annually) and from which we can discover much about 
past occurrences of drought, seasonal changes, 
atmospheric compositon, fire, and wind (Figure 4.1-F). 

Screw palms (Pandanus spp.) of the tropics develop 
ascending stem spirals, very reminiscent of fan turbine 
blades, and sunflowers create open seed spirals (in two 
directions), so common in many whorled plants. The 
stem itself forces open an ever-expanding flow 
through the X-Y plane between the media, allowing 
more material to pass through as time accumulates. 
The event expands the initial rupture of the surface 
between the media, allowing greater flow to take place, 
and this too is recorded in the target pattern of the 
stem, at the point of germination of the event (O). 



A set of intersecting sine waves developed over a 
regular square or hexagonal matrix will set up a 
surface composed of our core model shapes. It doesn't! 
matter if we see the sine waves as static or flowing, the 
core model will still maintain its shape, and flow in the 
system does not necessarily deform the pattern. Such a 
pattern matrix (Figure 4.2) shows that our models 
tessellate (from the Latin tesserae, meaning tiles) to 
create whole surfaces. If landscapes are, in fact, a set of 
such models, they must be able to tessellate. 

Convection cells on deserts arise from a roughly 
hexagonal matrix of air cells 1-5 km across, and 
matrices also underlie the spacing of trees in forests. 

Glacial landscapes show whole series of such 
patterns, as do regular river headwaters. We could 
equally well have created a matrix by adding in 
samples of our core pattern as we add tiles to a floor. 
Thus we see the Euclidean concept of points and lines 
underlies our curvilinear forms. Even irregular models 
(Figure 4.3) tessellate. Such tessellae are centred on 
nets or regular grids. 


FIGURE 4. 2 


Underlying many natural distributions (eg. trees in a desert, heat or 
convection cells) and forming many patterns (such as honeycomb and 

The "growth lines" (T-series) of our models are, in 
effect, a series of smaller and smaller forms nested 
within the larger boundaries, as is the case with target 
patterns or tree cross-sections. The process is termed 
annidation (Latin nidus, a nest) and is used in practice 
to compactly store bowls or glasses, one within the 
other; it then becomes a strategy for fitting-in like 
components of the same or different size in a compact 

If we superimpose two spirals of the opposite sense 
(spirals twisting in the opposite way), we develop the 
petal patterns of flowers and the whorls of leaves so 
common in vegetation, well illustrated by the seed 
patterns of sunflowers. The effect is also reproduced by 
simple reflection of such curves. 

Thus we see that tessellation, annidation, or 
superimposition gives us a strategy set for developing 
complex and compact entities, or for analysing 
complex landscapes. As Yeomans‘ 5> points out, ridges 
and valleys in landscape are identical reflections. If we 
model a landscape and pour plaster of Paris on the 
model, we reproduce the landscape in a reversed 
plaster model, but now' the ridges are valleys. 

Further, a set of our models invading into or 
generating from a portion of the landscape produce 
EXPANSION and CONTRACTION forms (Figure 4.4) 

cracks in mud) are matrices or grids based on approximate squares, 
hexagons, or intersecting sine waves 

typical of the edges of inland dunes and salt pans. This 
crenellated (wavy) edge produces edge harmonics of 
great relevance to design. 

The study of matrices reveals that the T (time) lines 
are ogives of a tessellated model and develop from the 
"S" (stream) lines of the next model adjoining. We then 
come to understand something of the co-definitions in 
our core model, and its inter-dependent properties. Sets 
of such models and their marginal crenellations provide 
a complex interface in natural systems, often rich in 
production potential. 

The earth itself is "a great tennis ball" (New Scientist , 
21 April 77) formed of tw’o core model forms. This 
earth pattern (Figure 4.5) of two nested core models can 
be re-assembled into a single continent and one sea if 
the present globe is shrunk to 80 % of its present 
diameter. My old geology professor, Warren ("Sam") 
Carey may have been justified in his 1956 assertion that 
the earth was originally that much smaller. When 
re-assembled in this way, the globe shows an origin 
("CT of our model) over each pole; the north polar 
origin is that of the seas, the antarctic origin that of the 
continents. At that time in earth history, all life forms 
were native to a single continent and all fish swam in 
one sea. 

The pattern has been shattered by a total expansion of 


the globe or by the spreading of oceanic plates cracking 
the continents apart rather like the net patterns on a 
mud patch, and isolating species for their present 
endemic development. The whole story is being slowly 
assembled by generations of biologists (Wallace, 
Darwin), geologists, and technicians analysing data 
from satellite surveys of the globe. 

The original pattern shattered, continents now drift, 
collide, and form their own life pattern by isolation, 
recombination, and the slow migration of natural 
processes. The process also illustrates how irregularities 
may arise on an expansion of a previously regular 
matrix of forms; tension caused by expanding 
phenomena shatters the smooth flow- of primary global 
events. At the end of a certain energy sequence, old 
patterns shatter or erode to make way for new patterns 
and succeeding forms of energy, as a decaying tree 
gives life to fungi and to other trees. 

_ 4 A _ 


Media, as a result of their chemistry, physical 
properties, or abstract characteristics, can be identified 
by us because they differ from each other. We 
distinguish not only air, water, earth, and stone but also 
hot, cold, salty, acid, and even some areas of knowledge 
as having different properties or validity. Every such 




Only two core models make up the geoid Each is deteclably higher 
than, or lower than, the other Origins lie near the poles, and when the 
continents are re-assembled we have one great continent and one 
great sea 

difference has a more or less well defined BOUNDARY 
CONDITION, surface, or interface to other media or 
systems. Permaculture itself acts as a translator between 
many disciplines, and brings together information from 
several areas. It can be described as a framework or 
pattern into which many forms of knowledge are fitted 
in relation to each other. Permaculture is a synthesis of 
different disciplines. 

Any such boundary is at times between, at times 
within, media, and (as in the case of the earth/air 
surface) these boundaries, surfaces, or perceptible 
differences present a place for things to happen, for 
events to locale. Thus, boundaries present an oppor¬ 
tunity for us to place a translatory element in a design, 
or to deform the surface for specific flow or translation 
to occur. 

If the media are in gaseous or liquid form, or com¬ 
posed of mobile particles like a crowd of people, swarm 
of flies, water, or dust clouds, then the media are 
themselves capable of flow and deformation. 

In nature, many such media and boundaries can be 
distinguished. As one example, a pond (with part of its 
margin) is shown in Figure 4.6. 

Although differently named (or not named at all), all 
these surfaces, edges, and boundaries separate different 
media, ecological assemblies, physical states, or flow 
conditions. Every boundary has a unique behaviour 
and a translation potential. Living translators (trees, 
fish, molluscs, water striders) live at each and every 

boundary. We can see that the establishment of complex 
boundary conditions is another primary strategy for 
generating complex life assemblies and energy 

"Most biologists," (says Vogel, 1981) "seem to have 
heard of the boundary layer, but they have a fuzzy 
notion that it is a discrete region, rather than the dis¬ 
crete notion that it is a fuzzy region." 

B.Quada[y/Edfle_D.esian Strategy 

The creation of complex boundary conditions is a basic 
design strategy for creating spatial and temporal niches. 



Boundaries are commonplace in nature. Media are 
variously liquid, gaseous, or solid, in various states of 
flow or movement. They have very different inherent 
characteristics, such as relatively hotter, more acid, 
rough, harder, more absorbent, less perforated, darker, 
and so on. Even in abstract terms, society divides itself 
in terms of sex, age, culture, language, belief, 
disciplines, and colour (just to enumerate a few 
perceived differences). 

In this confusion of definitions, social and physical, 
we can make one statement with certainty. People 
discriminate (in its true meaning, of delecting a 
difference ) between a great many media or systems, and 
therefore recognise boundary conditions or "sorts”, 
enabling them to define like and unlike materials or 
groups in terms of a large number of specific criteria. 

Differences, whether in nature or society, set up a 
potential STRESS CONDITION. This may demonstrate 
itself as media boundary disturbances, friction, shear, or 
turbulence caused by movement, sometimes violent 
chemical reactions, powerful diffusion forces, or social 
disruption. Seldom do two different systems come in 
contact without a boundary reaction of one sort or 
another, as quiet as rust, as noisy as political debate, or 
as lethal as war. 

If we concentrate our attention on the boundary 
condition, there are, crudely, two common or possible 
motions or particle flows—ALONG or ACROSS 
boundaries. In longitudinal flows (shear lines) between 
media, deflections and turbulence may be caused by 
local friction or the more cosmic Coriolus (spin) force. 
In crossing a boundary between media, the surfaces 
themselves may resist invaders (chemical or social); or 
various nets, sieves, or criteria may have to be 
by-passed by a potential invader. 

However, these boundaries are, in nature, often very 
rich places for organisms to locate, for at least these 

• Particles may naturally accumulate or deposit there 
(the boundary itself acts as a net or blockade). 

• Special or unique niches are available in space or 
time within the boundary area itself. 


• The resources of the two (or more) media systems 
are available at the boundary or nearby. 

Special physical, social, or chemical conditions exist 
on the boundary, because of the reaction between the 
adjacent media. As all boundary conditions have some 
fuzzy depth, they constitute a third media (the media of 
the boundary zone itself). 

This last statement is especially true of diffusive or 
flowing media, and of turbulent effects. Turbulence, in 
effect, creates a mix of the two or more media which 
may itself form another recognisable medium (e.g. foam 
on water, an emulsion of oil and water). 

In our world of constant events, especially in the 
living world, more events occur at boundaries than 
occur elsewhere, because of these special conditions or 
differences. It is common to find that there are more 
different types of living species at any such boundary or 
edge than there are within the adjoining system or 
medium. Boundaries tend to be species-rich. 

This "edge effect'* is an important factor in 
permaculture. It is recognised by ecologists that the 
interface between two ecosystems represents a third, 
more complex, system which combines both. At 
interfaces, species from both systems can exist, and in 
many cases the boundary also supports its own species. 

Gross photosynthetic production is higher at inter-faces. 
For example, the complex systems of land/ocean 
interface—such as estuaries and coral reefs—show the 
highest production per unit area of any of the major 
ecosystems (Kormondy, E.J., 1959, Concepts of Ecology. 
Prentice Hall. NJ, USA). 

Forest/pasture interfaces show greater complexity 
than either system in both producers (plants) and 
consumers (animals). It seems that the Tasmanian 
Aborigines burnt forest to maintain a large interface of 
forest/plain, since these transitional areas provided a 
great variety and amount of food. Animals are found in 
greater numbers on edges, for example, and a fire 
mosaic landscape is rich in species. Such mosaics were 
the basis of Australian Aboriginal landscape 

In view of the edge effect, it seems worthwhile to 
increase interface between particular habitats to a 
maximum. A landscape with a complex edge mosaic is 
interesting and beautiful; it can be considered the basis 
of the art of productive landscape design. And most 
certainly, increased edge makes for a more stimulating 
landscape. As designers we can also create harmonic 
edge with plants, water, or buildings. 

There are aspects of boundaries that deserve con- 

FIGURE 4. 6 


We can distinguish between many conditions or torms o' media (air. 
water, earth, mud), physical conditions ('low. heat, salinity), and we 
can manipulate adjacent systems (lores!, water, crop, grassland, 
gravels) to produce landscapes rich in borders, hence species and 

1 air/water 
4 flowmg/still 
7 anaerobic/subsoil 
10 brackistvsalty 
12 catchment/catchment 

2 Iresh/brackish 3 warm/cool 

5 grass/water 6 marsh/water 

8 soit/subsoil 9 stream/bank 

11 stream order/sub order 
13 torest/water 14 water/mud 


siderable design intervention: 

• The geometry or harmonies of any particular edge; 
how we crenellate the edge. 

• Diffusion of the media across boundaries (this may 
make either a third system or a broader area in which to 
operate-few boundaries are very strictly defined). 

• Effects which actively convey material to or across 
boundaries; in nature, these are often living organisms 
or flow (bees, for example). 

• The compatibility (or allelopathy) of species or 
elements brought into proximity by edge design. 

• Boundaries as accumulators on which we can 
collect mulch or nutrients. 



The amplitude, configuration, and periodicity of an 
edge, surface, or boundary may be varied by design. 

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Least path - design tor home gardens, a keyhole pattern (common in 
nature) allows us to access garden beds most efficiently. Parallel 
paths take up to 50% ot the area; keyhole beds <30% ot the ground. 
(See also FIGURE 10.26 Gangammas Mandala). 

Edges and surfaces may be sinuous, lobular, serrate, 
notched, or deliberately smoothed for more efficient 
flow. While we may deliberately induce turbulence in 
salmon streams by using weirs, we are painstaking in 
using smooth and even conduits for energy generation 
in wind or hydraulic systems. We can deepen areas of 
shallow streams to make pools, or to prevent stream 
bank erosion, or to reflect sun energy to buildings; all 
these are manipulated to achieve specific effects on their 
boundaries or surfaces. 

Notched or lobular edges, such as we achieve in plan 
by following hill contours, afford sheltered, wetter, 
drier, hotter, or more exposed micro-habitats for a 
variety of species. Serrate or zig-zag fences not only 
stand on their own, but resist wind-throw much better 
than straight barriers. Lobular embayments, like the 
keyhole beds of Figure 4.7, are obviously sheltered, 
spacious habitats for gardens and settlements. 

As for surface and flow phenomena, we can partition 
water surfaces to reduce wind effect, or design to 
deliberately create turbulence and wind overturn. 
Islands, quoins, and rafts of many shapes have as many 
uses, and deflect flow to increase condensation or to 
encourage sand and snow deposition or removal. 
Surfaces can be pitted, ridged, spiralled, mounded, 
tessellated, tassled with plants or brush, paved, sprayed 
to stabilise mulch, mulched, or smoothed for water 


Without altering the area ol a field and a pond, we can double the 
plants on the pond-edge (e g. blueberries) by crenellatmg this edge to 
increase the earth/water interface 

When a boundary separates two things which differ, 
there is an opportunity for trade, transactions, or 
translation across the border. Where the boundary itself 
is difficult to pass, where it represents a trap or net, or 
where the substances and objects attempting to pass 
have no ability to do so, accumulations may occur at the 
boundary. Examples of this lie all about us, as stranded 
shells on the beach, people lined up at visa offices, and 
cars at stop lights or kerbsides. 

People are, at heart, strandlopers and beach-combers; 
even our dwellings pile up at the junction of sea and 
land, on estuaries ( 80 % of us live at water edges), and at 
the edge of forest, river, marsh, or plain. Invariant 
ecologies may attract the simple- minded planner, but 


they will not attract people as inhabitants or explorers. 

In design, we can arrange our edges to net, stop, or 
sieve-through animals, plants, money, and influence. 
However, we face the danger of accumulating so much 
trash that we smother ourselves in it. Translators keep 
flow on the move, thereby changing the world and 
relieving it of its stresses. The sensible translator passes 
on resources and information to build a new life system. 

There are innumerable resources in flow. Our work as 
designers is to make this flow function in our local 
system before allowing it to go to other systems. Each 
function carried out by information flow builds a local 
resource and a yield. 

If you now carefully observe every natural 
accumulation of particles, you will find they lie on edges, 
or surfaces, or scattered nearby, like brush piled up 
against a fence (Figure 4.9). We can use these processes 
to gather a great variety of yields. 

It follows that edges, boundaries, and interfaces have 
rich pickings, from trade both ways or from constant 
accumulations. Our dwellings and activities benefit 
from placement at edges, so that designing differences 
into a system is a resource-building strategy, whereas 
smoothing out differences or landscapes a deprivation 
of potential resources. 

Objects in transit can be stopped by filters and nets. 
The edges of forests collect the aerial plankton that pass 
in the winds. Boundaries may accumulate a special 
richness of resource, as a coral reef collects the oxygen 
and energy of the sea, and the canopy of the trees the 
energy of the wind. We rely on translators, such as trees 
and coral, to store such impalpable resources, to process 
them into useful products, and to store them for use in 
their own system, with some surplus for our essential 

Transactions at boundaries are a great part of trade 
and energy changes in life and nature. It seems that 
differences make trade; that every medium seeks to 
gather in those things it lacks, and which occur in the 
other medium. However, we should also look at the 
translator, which is often of neither medium but a thing 
in itself, the "connection or path between", created from 
the media, but with its own unique characteristics. 

Plants, people, and pipes are translators. Nets, sieves, 
passes, and perforations are openings for translators to 
use, and (as traders know) there is no border so tight 
that a way does not exist for trade. Go-betweens or 
traders, like many plants and animals, are creatures of 
the edge. They seek to relieve the stresses caused by too 
much or too little in one place or another; or to 
accumulate resources (make differences) if they operate 
as storages. We can use naturally-occurring turbulence, 
trade, and accumulations to work for us, and by 
carefully observing, find the nets and go-betweens of 
use. We can use naturally-occuring turbulence, trade, 
and accumulations to work for us, and by carefully 
observing, find the nets and go-betweens of use. 

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At powerlines and fences, perched thrushes and wood pigeons 
defecate, so that each post gains seed and manure, and each may| 
generate a plant from nearby forests. Perches plus disturbed soil 
produce this result Fences also act as mulch accumulators across 

_4 J _ 


There are only limited interactions possible between 
two abstract or real systems brought into boundary 
contact. The sum of possible effects available are these: 

• No difference in yields, stability, or growth (o,o) 

• One benefits, at the expense of the other (+,-) (-,♦) 

• Both benefit (+,+) 

• Both are decreased in yield or vitality (-,-) 

• One benefits, the other is unaffected (+,o) (o,+) 

• One is decreased, the other is unaffected (-,o) (o,-) 

Almost all organisms or systems get along fine. A 

great many derive mutual benefit, and a very few 
decrease the yield of others or wipe each other out. It 
simply doesn't pay to attack others. In the long run one 
destroys oneself by accumulated injury or, more 
certainly, by pathogens in an animal or conflicts within 
a society that await a monocultural crop or repressive 
society. For our domestic plant groups, a powerful 
design strategy for yield and system stability is to select 
compatible components for complex edge and surface 

Many crops, like wheat and pulse grains, trees which 
bear on the crown, and mass-planted vegetable species, 
yield much better on the crop edge than they do within 
the crop. Taking examples where edge yield is marked 
(e.g. in wheat, lucerne); where there is a (+,+) 


relationship, as is the case of crops such as wheat and 
lucerne (alfalfa); and presuming a two-fold yield 
increase on edges (it can be more for such trees as 
Acacias with hazelnuts), we can proceed as follows. 

First, we need to measure just how far into each crop 
the edge effect extends, so that we can estimate a finite 
width of higher yield. We will assume 1 m for wheat 
and the same for lucerne, giving a 2 m width as a 
double edge. It is now quite feasible to sow a field in 2 
m wide alternate strips of each crop, giving us (in 
effect) nothing but edge, and obtaining from this field 
about the same yield as we would have had we sown 
twice the area to single crop stands (Figure 4.10). 

Two crops are a simple example, but if we extend the 
principle to many and varied crops on an even broader 
scale, we approach a new concept of growing, which 
we can call ZONE or EDGE CROPPING. These would 
produce a matrix of hedgerows or edge-rows, each 
suited in width to a particular crop. Such zonal strips 
are seen naturally occurring on coasts and around 
saltpans or waterholes. 

This sort of setup might be a nightmare for the 
bulk-cropper (or it may not), but has immense 
potential for small shareholders in a single land trust, 
each of whom tend one or more crop strips. It is very 
like the older patterns of French-intensive agriculture 
and the farmed strips of modern Quebec, which 
produce a very productive crop mosaic. Polycultures 
can be composed of such mosaics or zonal strips. 

For cases of (-,-) interactions, both crops suffer, but 
active intervention with a component acceptable to 
both systems may work: 

Place an intervening, multually-compatible component 
between two incompatible systems. 

Compatible components may simply differ in sex, 
colour, chemistry, belief, or political conviction from 
the warring parties. However, in time a beneficial 
mosaic will impose itself on all expansionist systems, 
arising from the potential for differences carried within 
all life systems. Natural interveners arise, often as 
hybrids between apparently antagonistic systems. Our 
design intention in landscape systems is to build 
interdependence into mosaics.. 

Select and place components so that incompatibity is 
nullified, interdependence maximised. 

After all, in the absence of tigers, Hindus need 
Muslims to eat cows; they may also need a Christian 
businessman between them to effect the transaction. 
The interdependence of mosaics of belief are called for 
as much as mosaics of plants. 

The stupidity principle may here be stated in a 
different way: 

Stupidity is an attempt to iron out all differences, and 
not to use or value them creatively. 

It is our skill in organising spatial or functional 
distribution that may create beneficial 
interdependence in incompatible components. When 
we know enough to be able to select mutually- 
beneficial assemblies of plant and animal species 

A MA oR_ 
■SToNfe re«'T 



FIGURE 4.10 


Fields of equal area, plants at the same inter-row and in-line spacing, 
but in (A) we can fit 36 plants, in (B) 45 plants. 'Straightness' can 
reduce yields. Modern machines are available that follow such paths 
in crop, or the pattern can be on a larger scale. 

A 36 fW? 


(guilds) then we have two powerful interactive 
strategies (edge harmonics and species compatibility) 
for design applications. 

Mosaic design (the opposite of monoculture) means 
the creation of many small areas of differences. A few 
mistakes will occur, but good average benefit will 
result. This was the tribal strategy. 

A Golden Rule q! Design 

Keep it small, and keep it varied. 

Our tree model is not only different from its supporting 
media, but exists because of them. Stress builds because 
of impermeable boundaries. If a fence allows mice 
through but restricts rabbits, it is the rabbit plague that 
will break it down. If too much money accumulates on 
one side of a door it will either force the door open of 
itself, or those deprived of it will break in. The terrible 
pressures that gases and molecules can exert are 
harmless only when that pressure is free to disperse, or 
where potentially destructive energies are quietly 
released where there are no boundaries, multiple 
translators, or stress-relief mechanisms. 

Because the event itself creates a third medium, it 
again sets up stress between itself and the media (Ml 
and M2). It can be seen, therefore, that once any one 
difference of any sort, even an idea, exists anyu>here, then it 
demands or creates conditions for the evolution of 
subsequent events. That first event itself became yet 
another difference, which in turn needed translation, and 
so on. The process is self-complicating, continually 
creating of itself all that follows, and all that continues. 
All is stress, or the relief of stress, and that stress and 
relief is located between existing differences. One 
difference in the beginning was enough to generate the 
total range of subsequent events. There are no "new” 
events, just a continual expression of all possible 
events, each arising from some recombination of 
preceding differences. There are no miracles, just a 

FIGURE 4.11 

DNA. coiled around a plus-torus like a single path in the Robinson 

realisation of infinite possibilities. Any event has the 
potential to spawn all possible events. 

There are no new orders of events, just a discovery of 
existing events. 

Every event we can detect is a result of a preceding 
event, and gives rise to subsequent events. 

Between all media, some DIFFUSION can take place. 
This is greatly enhanced by such phenomena as surface 
turbulence, wave overturn, temperature differences, 
and pressure differentials. Boundaries between 
diffusing media are blurred, often seasonally different 
or sporadic in occurrence, and always in flux. Plants 
give pollens and chemicals to air, and actively 
intervene in radiative, gaseous, liquid, and general 
energy transactions with the atmosphere. Between 
plant groups, leaf, root and mulch exudates diffuse as 
chemical messengers. Water is the 'universal solvent" 
of substances diffusing through the earth's crust, in 
plant systems, and in the atmosphere. 

Diffusion is a quiet process operating on a broad 
front or over the entire surface of some media. It is 
analagous to, but differs from, the active transport 
systems that we have called events or translators. 
However, once an event has occurred, it also uses 
diffusive processes to gather or distribute materials, 
and thus events merely enlarge the total diffusive area 
available. A tree may have many acres of leaf, and 
evapo-transpiration will then exceed evaporation at 
that place by a factor of forty or more. We can grow 
many such trees on one acre, and thus increase the 
diffusion effect by factors of 1000 or more, so that 
gaseous exchange from leaves, and sugars in soils (or 
soil life) are both assisted by the trees. 

_4 I 8_ 


We can see how an event takes place, but how is it 
shaped? Our bodies arise from the origin (O) of a 
zygote (a fertilised egg) on the surface of the uterus; 
the placenta is our root, the foetus the tree of our¬ 
selves. Animals are thus events broken free from the 
coiling connective cord or umbilical stem of their 
origins. Their eventual shape is a pattern laid down or 
encoded by the DNA of their cells, coiled as it is 
around a plus-torus like a ribbon around a doughnut 
(Figure 4.11). 

When my son Bill was four, we were in the bath 
together, and he pointed to his toes. "Why are these 
toes?" he asked. 

"What do you mean?" I hedged. 

"Well, why don't they get bigger and bigger or longer 
and longer? Why do they stop at being toes?'' 

What limits size and growth? All flows pulse, 
whether they are blood, wind, water, lava, or traffic. 


The pulsing may be organised by PULSERS (e.g. traffic 
lights), and results in WAVES, or time-fronts, or 
particles on fixed schedules. Such pulsers (Figure 4.12) 
are located in our bodies as chemical or 
physio-chemical spirals in sheets of cells that swirl in 
sequence to create a pulsing movement in our heart, 
organs, and viscera. Pulsers can start, run for a preset 
time, and stop. This is how we grow, and why we 
eventually die. All mammals have an allotted number 
of heartbeats in relation to their body size, and when 
these run out, we die. (A friend also theorises that we 
have a set quota of words; and when they are said, we 

FIGURE 4.12 

Pulsing, here trom Wmtree s •doped' chemicals, may take the form of 
spirals revolving about a locus, in this case centripetal in action like a 
low pressure wind cell Pulsing is regular in these chemical systems, 
as in muscle or flow phenomena. 

Pulsers plus patterns account for shapes. They 
determine that a toe will stop at being a toe, and not 
grow into a monstrous appendage or stay as a midget 
toe. Thus, all living events carry their characteristic 
time-shape memories, and (it would appear) so do 
rivers, volcanoes, and the sun itself. The sun ' pulses'' 
every 11 years or so, affecting our ozone and climatic 
factors such as rainfall. Our own pulses have 
characteristic or normal resting rates, as do our 
peristaltic or visceral movements. 

Pulsers act in concert to create peristaltic or heart 
contractions, but if they get the wrong signals, can 
move out of phase and send the organ into seizure. 
This spasm may cause damage or death (a heart 
attack). The pulses drive fluids or particles through 
vessels or arteries in cities and in bodies, and those 
then branch to serve specific cells, organs, or regions. 

Figure 4.12 is a quite extraordinary spiral pattern 
which arises from the pulsing reactions of organic 
acids seeded with ionic (iron, cerium) catalysts. The 
pulses are quite regular, "at intervals of about a minute, 
but these may vary up to 5 minutes in living systems 
such as nerve tissue and a single layer of a social 

amoeba" (Winfree, 1978, "Chemical Clocks: A Clue to 
Biological Rhythm" New Scientist , 5 Oct 78). The 
system is one of spirals rotating about a pivot point 
which is not a source but an invariable locus around 
which a spiral wave is generated. It is sequences of 
such phenomena that create a peristaltic system. 
Spirals of this nature can revolve in two senses: either 
organising material to the pivot, or (revolving in the 
opposite sense) dispersing material to the periphery. We 
can envisage counter-rotating spirals doing both as 
they do in the circulation of the atmosphere as high or 
low pressure cells. 

The phenomena is shared by nerve, heart, and brain 
tissue; organic and inorganic oxidation on two- 
dimensional surfaces; and in thin tissue subject to 
exciting stimuli. Ventricular fibrilation (a potentially 
fatal quivering of the heart) may derive from the spasm 
effect distributed over heart or nerve tissue, causing an 
ineffectual churning" (Winfree, ibid). It may also 
account for involuntary spasm in muscle. Spasms can 
damage the cells of blood vessels, and cause a 
build-up of scar tissue or cholesterol at the injury site, 
or in muscle tissue—an area of hard waste products. 
The social amoeba Dictyostelium uses the pattern to 
move towards the pivot point where "they construct a 
multi-cellular organism which then crawls away to 
complete the life cycle" (Winfree, ibid.), a process 
resembling the precursor of hormonal control in the 
nervous system. Some such process may assemble 
more complex multi-species organisms like ourselves. 

The cycling spirals can be found in biological clocks, 
such as those which govern the 24-hour metabolism of 
flowers and fruit-flies, stimulated by oxygen or light 

Within a specific organism, specific pulsers exist; the 
24-hour rhythm (CIRCADIAN) of birds is controlled 
by the pineal gland (New Scientist, 11 Oct '84) which 
secretes a regular nocturnal pulse of the hormone 
MELATONIN (the changing levels of melatonin trigger 
the annual cycles of breeding and nest-building in 
birds). Visual perception of light changes and day 
lengths regulate the production of melatonin in the 
pineal gland. Even small pieces of the gland in 
isolation will respond to light, and can be disrupted by 
flashes of light (as in lightning) at night. Thus, we see 
that not only expansion, but DISCHARGE 
PHENOMENA such as lightning (or sudden shock in 
people) disrupt or trigger initiatory reactions in life 
rhythms, and introduce irregularities in cycles or 
pulsers, just as expansion or shock introduces 
irregularity in fixed forms. The question arises as to 
whether the disturbance produced by shock or sudden 
stimulus is responsible for expansions, cyclic changes, 
or shape deformations on a more general scale. 

Species and individual organisms need both 
SHAPERS (DNA) and TIMERS (biological clocks) to 
achieve a specific size and shape. The two must work 
synchronously to achieve the correct proportions of 
parts such as fingers and toes, but both are critical to 
the organism. 


Branching patterns in bodies must have (already 
encoded) the correct angles and placements for their 
mam branches, leaving room for sideshoots and forks, 
but not for interweaves or cross-points which damage 
the function of the organism. In order to generate the 
surface or boundary of a person, and their reticulation 
systems, patterns of incredible complexity and strict 
limits must be "known" by the cells or the cell 

We ourselves are part of a guild of species that lie 
within and without our bodies. Aboriginal peoples and 
the Ayurvedic practitioners of ancient India have 
names for such guilds, or beings made up (as we are) 
of two or more species forming one organism. Most of 
nature is composed of groups of species working 
mterdependently, and this complexity too must have 
its synchronistic regulators. 



Implicit in many of the phenomena discussed are the 
forms of spirals. These may be revolving (dynamic) or 
fixed (static), and arise as a consequence of deform¬ 
ations in flow, or are rather an intrinsic property of a 
specific velocity of flow over surfaces. Other spiral 
paths are traced out by orbiting bodies over time, or 
are shapes developed by organisms developing a 
compact form (e.g. molluscs) that is analagous to 
annidation. Spiral forms are made visible by plants as 
whorls of leaves and branches. 

D’arcy Thompson (1952) in his book On Growth and 
Form, discusses some of the quantitative or geometric 
qualities of spiral phenomena, which are hidden or 
revealed in many natural forms. A long spiral in 
section is the "S" form of humid landscape slopes (and 
the yin-yang symbol). Three-dimensional spirals form 
long ribbons of complex shape. Even within the 
molecular forms of matter, DNA reveals a double¬ 
helix form. Spirals are, in effect, single streamlines of 
vortices, tori, or sap flows. 

Spirals arise from the interaction of streaming and its 
subsequent deflection of flow around vortices. Storl 
(1978, Culture and Horticulture. Biodynamic Literature 
Rhode Island) points out the spiral arrangement of 
leaves in many plants, where leaves are from one-half 
way, one-third way, and so on around the stem from 
the preceding leaf, or to the next leaf. Such placements 
may progress in a regular (Fibonacci) series, each 
following on from the sum of the two preceding ratios: 

1:2 * 1:3 = 2:5; 1:3 + 2:5 = 3:8, etc., so we get 5:13, 8:21, 
13:34 and onwards. These sequences are found in 
plants and in planetary orbits, so that "Venus forms 
five loops (retrogressions) below the ecliptic in eight 
years." Storl sees a relation between the forms of plants 
and of planets in these progressions, as we can see in 
the orders of size. 

Like so many real-life phenomena, natural spirals 
are not "perfect”, but "show slight progression" and 
gradually lose phase over long periods (Storl, ibid). We 
can often use the spiral form in design, both to create 
compact forms of otherwise spread-out placements 
and to guide water and wind flows to serve our 
purposes in landscape. We can see the application of 
spiral forms to technology in everyday life as screws, 
propellers, impellers, turbines, and some gears. Some 
species of sharks and invertebrates develop spiral gut 
lining to increase absorption, or spiral cilia to convey 
mucus and food or particles in or out of the organism. 
Plants such as Convolvulus use spiral anchors in earth, 
as do some parasites in animal flesh. 

Thus, spirals are found where harmonic flow, 
compact form, efficient array, increased exchange, 
transport, or anchoring is needed. We can make use of 
such forms at appropriate places in our designs. 



The simple involuted mushroom, called an "Overbeck 


# mm* 

X J 




Regular and usual galaxies have limited lorms (eliptical. 


V ^ 

spiral, or barred) and slow rotations Even galaxies can be 
ordered in terms of form. 


jet" by D'Arcy Thompson (1942). is also shown in its 
"apple core" model form in Figure 4.13. While we can 
produce these patterns by jetting smoke, fluid, gases or 
oils into other media, they occur as a part of the natural 
streaming of fluids and gases past fixed objects such as 
bluff bodies (e.g. posts) in streams, islands in tides, and 
trees in wind. Jet streams at altitude can generate such 
vortices by pushing into different air masses, as can 
muddy water entering the sea. 

FIGURE 4.13 

The Overbeck jet is a simple halt-form ot the basic model, and occurs 
commonly in nature e g mushrooms, rivers Hooding into the sea. and 

Whirlpools or VORTICES are shed alternately from a 
fixed bluff body located in flow, each side generating 
its own vortex, each with a different rotation. Beautiful 
and complex forms are thus generated (Figure 4.14 ) 
and these are the basis of the work at the Virbela 
Institute on flowforms. The sets of vortices shed or 
generated downstream from fixed bodies in flow are 
called Von Karman trails. 

The trails are stable at the 1:3.6 ratio shown in Figure 
4.14. In many streams, and on foreshores, the 
clay-beds, silts, and underlying rock may develop such 
patterns, and posts fixed in streams commonly 
produce them in water. Trees and windbreaks produce 
similar effects in wind, as do waves at sea. In wind, 
they are called EKMAN SPIRALS, and in air the spiral 
lift effect compresses air streamlines to a height 20-40 
times the height of the tree or fence fixed in the air 

It is obvious that the stable spirals of the Von 
Karman trails will produce successive pulses down¬ 
stream, and this is in fact how we observe most flow 
phenomena to behave. Thus the pulsing of wind, 
water, and flow in general may rely on the elastic or 
deformation properties of the medium itself rather 
than on electro-chemical "timers" as found in organ¬ 
isms. In nature, there are many fixed impediments to 
perfect streamlined flow. 

It is typical of Von Karman trails generated from a 
fixed body that the effect persists as 4-5 repeats (Figure 
4.14. C), and then the stream of water gradually 
resumes streamlined flow. At higher velocities of 
stream flow, chaotic turbulence occurs, and at slower 
velocities, simple streaming persists around objects. 
Thus we see that the Von Karman trail is just one form 




4 “ 

CRgA 5c P 
L o w 

FIGURE 4.14 


At certain modest How speeds, water, wind, and even clouds torm a 

stable 4 to 5 series train called a Von Karman trail: such phenomena 
were vital guides to Polynesian navigators (see Figure 4.26). 



FIGURE 4.15 

A bluff body drawn through still water can make a theoretically endless 
trail ol Overbeck jet forms, superficially resembling a Von Karman 



FIGURE 4.16 


The effects of fixed bodies on wind, waves, tides, and cloud streets; 

of patfcm generated by specific flow conditions. It is 
nevertheless a common form in nature. 

The spiralling of wind over tree lines produces a 
secondary effect, analagous to the streaming of tides 
around atolls; the wind changes direction past the 
obstacle (about 15°). Such effects may occur within 
media of different densities (temperatures) as when 
warm high-pressure wind cells ride over colder low- 
pressure fronts. The temperature, pressure, and 
velocity of wind or gas systems are often related; 

• Low pressure - high velocity - cool temperature - 

• High pressure - low velocity - warmer tempera¬ 
ture - (contraction). 

Velocity in gases and fluids «s strictly governed by 
contact with stationary surfaces, so that the velocity is 
effectively nil very close to static surfaces, increasing 
as a series of (imaginary) laminar sheet flows above 
that surface (Figure 4.i7). This is the effect that is 
observed in viscous flow in small canals or vessels, and 
that governs the shapes and strategies of organisms 
such as limpets and starfish. 

Thus, we see that media in flow can produce pulsers, 
vortices, and spirals as a result of irregular or 
obstructing objects or resistant media, and that these 
phenomena are interconnected. 

The relationships between fluid flow, boundary con¬ 
ditions, and the form these impose on organisms is 
clear from our pattern models and their deflection 
states. Life as evolved by its internal and external 
patterns and flows is very well discussed by Vogel 
(1981) in a lively and scholarly book entitled Life in 

various phenomena arise from How lorms. 

Moving Fluids. 

Carried in the flow of media, as a thistle-down in air, 
are many events looking for a place to happen. A "net ’, 
resting surface, or detonator is needed for these 
potential events to express themselves. We can pro¬ 
vide many such receptors or triggers in our design 
systems, catching nutrients in flow and ensuring 
events for future growth in our system. Some such nets 
form starting-places for events, while others are 
resting or death places for those entities dependent on 
flow, or stranded out of their nutrient media. 

Just as a series of corks floating on the sea have a 
predictable path to shore perpendicular to the wave 
fronts, so does matter flow in a wave-tank model. 
Similarly, drift-lines form at sea (STREAMLINES in the 
core model), and as these end on shorelines, they 
deposit or remove material. 

It is along these streamlines that energy acts, by 
medium of the waves of growth or surface waves in 
motion. This is how the event and its material ex¬ 
pands: streamlines diverge as wave fronts and 
disseminate into open media, but are strong, concen¬ 

trated, and visible at constrictions, near origins, or in 
powerful or refracted flows. A small restricted orifice 
in the time-front or wave-front acts as a secondary 
origin. Just as a grub encircling a tree causes it to 
branch out at that point, so constrictions in the flow of 



A-* D Fuow WCR6AS/NCa- 



A & 

lamina flow CAmjz vortices 

A—»D Plow /MCREASiMG . 

FIGURE 4.18 


Flow at different velocities produces different downstream 
phenomena Here velocity increases from A - D. as wind over an 
isolated island, or current flow past an atoll. 

To pRottfEVoN 
("RATIO ib l) 


NOTE- NMtfoL/iA/G 


events generate secondary origins. I once watched this 
happen with a eucalypt that I planted in 1953, and saw 
it twin and twin again as swift-moth grubs encircled 
:ts stem. It is now a mighty tree, much branched, but 
the evidence of these minute constrictive events are 
still buried in its stem. As designers, we can impose 
small constricting events or place fixed objects in flow 
to produce such specific results. We can then be the 
external shapers of patterned events. 



Creatures that live in open flow conditions are 
specially shaped and adapted to surface or low-flow 
(high pressure) phenomena, and may erect or develop 
"chimneys' to draw fluids or gases through their 
burrows or bodies. Some life forms combine chimneys, 
spirals, and crenellations to effect an exchange between 
them and their fluid surrounds (Vogel, 1981). 

All of these effects of flow are of great relevance to 
designers, engineers, and biologists, and their effects 
can be increased, nullified, or decreased by design. 
Natural effects can be used in a variety of ways, and 
the effects of orders may impose limits on design. 
Further data is given under Chapter 6: Trees and 
Energy Transactions". 


*56 H4SS or a -AlAiU- 

Piaw oe utfpe^soiWAce- 
cc -SOA'L (G6 

PCAM or Top^r«*ce 
op a/A/t R2: 

FIGURE 4.19 

(Arrows represent wind or water speed). Pressure is high near the 
surlace. lower at a distance, thus a starfish (or a chimney) experiences 
a flow 'under and out the top' in flow conditions. The sand snail egg 
mass is built to be easily irrigated, the starfish gets food in the water 
stream by their configuaralion in flow 

FIGURE 4.20 

Pattern for an electron, a massless particle, travelling up this page at 
the speed of light: energy as form, congruent also with the general 

I /tutcfaor+AneKc. 

FIGURE 4.21 


A simplified model of a dense planetry body (c.f. the general model). 
Electro-magnetic fields and thermal convection create special 
conditions along the axis of spin. Many such bodies emit material at 
the poles before cooling. 


_4 1 12_ 


Implicit in our core model, and obvious in violent 
detonations such as atomic explosions, puffs from 
diesel exhaust pipes, or deliberately blown as smoke 
rings, are the rolling doughnut-shapes of TORI. A 
TORUS is a widespread natural phenomenon. The 
closed models (Figure 4.13) enclose such a torus, and 
we can imagine a slow-cycling torus of nutrients 
surrounding the stem of any tree as crown-drip carries 
nutrients to the ground, and the roots again return 
them via the stem of the tree. 

Photographic stills of atomic explosions may reveal 
violently rotating tori around and crowning the 
ascending column of smoke and debris. Violent 
up-draughts caused by local heat create such tori in 
atmospheric thermals, much appreciated by soaring 
birds and glider pilots, who ride the inner (ascending) 
circle of the doughnuts of hot air that are generated, for 
example, over deserts on hot afternoons. 

A complex toroidal form is the "Robinson Con¬ 
gruence" (Figure 4.20), portraying the space-time form 
of a mass-less particle such as a proton, representing, 
in effect, annidated tori. 

DNA is also portrayed as encircling such an 
imaginary plus-torus in Figure 4.11. A Mobius strip—a 
one-sided twisted toroid (often portrayed by M.C. 
Escher in his art)—enables us to cross an edge without 
lifting our pencil. Many life forms produce tori (e.g. 
some sea snail egg masses). We rely on a torus of 
rubber to inflate our tyres and to seal circular hatches 
as O-rings. 

A torus is, in effect, a special or truncated case of the 
Overbeck jet (Figure 4.13), as a foetus is a truncated 
"tree", and can be generated by discontinuous or 
explosive flow, or pulses in flow. A torus is a closed 
three-dimensional vortex. One such closed toroidal 
form, as found in black holes, is shown in Figure 4.21. 
Here, accretion of matter causes gaseous ejection at the 
poles, as the earth may have "ejected" seas and 
continents at the magnetic poles, or gathers in the 
violent energy of ionised particles that form the 
auroras, visible as polar tori in satellite images. Even 
the long curtains of the auroras seen from the ground 
contain vertical spiral columns (J. Reid pers. comm.). 

_ ^13 _ 


Our patterned systems may exist in two or more 
dimensions. We can tessellate two-dimensionally but 
need to envisage three dimensions for a tree form or 
glacier. The tree-forms of rivers flow down along 
S-shaped gradients; the generator of such a pattern is 
gravity. Sand dunes form on near-flat platforms of the 
desert, and have wind as their generator, as do waves 

on the sea. Neither gravity nor wind may much affect 
the creeping tree patterns of mosses, dendrites in 
shales, or the tree-like forms of mycorrhiza in plant 
cells. It is here that we see our tree form as the best way 
to grow or to gather nutrients in the absence of violent 
kinetic processes. The generator here is life or growth 

When kinetic forces do not act strongly, as in flat and 
essentially sheltered desert environments, lobulation 
and latticing still occur as freeze-thaw or swell-shrink 
patterns, as they do in ice floes on quiet ponds or in the 
hexagonal patterns of stones on tundra. The slow 
growth of crystals into rock cavities or ice is still related 
to our general model; the generator of pattern here 
being at the level of molecular forces, as in many 
purely chemical processes, and the forms generated are 

In hill country, energies are usually a combination of 
stream flow and gravity. On plains, icepacks or flat 
snowfields, it is freeze-thaw or the swelling of clay in 
rain that produces lobulations or networks of earth 
patterns. Lobulation, the production of such shapes as 
in Figure 4.7, differs in origin and mode of expression 
from the kinetic-energy (flow) systems we have been 
discussing. 1 sometimes think of the lobulated forms as 
a response of nature, or life, to a world that threatens 
"no difference". 

If the hills wear down, then the antepenultimate 
surfaces will produce their lateral, two-dimensional 
life patterns, as does the lichen on a rock. Kinetic 
erosion processes are then exchanged for physical and 
chemical process at the molecular level, but even this 
creates a sufficient difference in media for life forms to 
express themselves, and for differences to arise in the 
patterns of surfaces. 

_4 I 14_ 


Although trees (including tree roots) may approach 
spherical form, the best examples are found in 
spherical bodies in space. These deflect light, dust, and 
gas towards them, and may capture materials. In their 
early formation, they themselves may have had dense 
cores that assembled their share of galactic materials, 
and around these cores a torus of matter of low- or 
high-speed rotation can form. This is the model 
presented for most bodies (New Scinetist, 4 April 85, 
pp. 12-16). A general model is given in Figure 4.21. 

As matter accumulates in this way, bodies can 
respond by: 

• Becoming more dense- to a limit of 10 u g/cm 3 ' 

• Swelling or expanding (producing shatter effects); 

• Ejecting material at the poles. 

Or any combination of these depending on the state 

of the matter attached or attracted to the core. 

For pulsars, the ejection is radio waves, and for black 
holes high-speed gas plumes. For trees, of course, we 
find expansion and transpiration, not localised to the 
axis of growth. 

However, along the Z-Z (ejection) axis of Figure 4.1, 
rotating tori speed up ejection at north poles, and slow 
it down at south poles, so that less viscous materials 
are likely to be emitted at north polar emitters. This 
general effect may be portrayed in one model, but each 
case needs study. Weak gravitational waves permeate 
the astronomical system as pulsers permeate or 
orchestrate biological systems, aiding both dispersal 
and accumulation depending on the sense of rotation 
of the accreting system, or the electromagnetic fields 
interacting with incoming particles. It seems probable 
that weak fields within the sun creates its pulsers, 
which proceed from pole to equator as a roll or torus of 
turbulence over an 11 -year period. 



Various sections, plans, and views of our one tree 
model reveal very different sectional PATTERNS, all of 
which are inherent and most of which recur in many 
other natural forms. Benoit Mandelbrot assembled his 
own insights, and the speculations of others, to found a 
mathematics of fractals (his term, from the Latin 
fractus, or shattered), which is evolving to make sense 
of irregular phenomena, as Euclid did for more regular 
and measurable forms (New Scientist, 26 Apr '84, p.17 
and 4 Apr 85, p.31-35). 

Fractals are as common in nature as in abstractions, 
and examples are as diverse as impact shatter-zones, 
clouds, forked lightning, neurone nets and their 
signals, computer searching procedures, plant 
identification keys, snowflakes, and tree branches or 

roots. Some typical fractal forms are illustrated (Figure 
4.22). Others make up the complex lengths of coastlines 
and the intricacies of turbulence. 

In our tree form (Figure 4.1), these fractal patterns 
(as branches and roots) are contained within a form 
that would be comprehensible to Euclid, having 
straight axes, a plane, and regular curved lines, which 
can be drawn as arcs of perfect circles. Thus the 
apparent chaos of fractals can be seen to underlie quite 
regular (but never perfect) shapes in nature as 
branches underlie the crown canopy of a tree. As 
Mandelbrot has demonstrated, fractals have their own 
regular generators and evolutions. 

▼ * 
* * 

FIGURE 4.22 

Fractal forms mat be generated by repetition of relatively simple form 
generators, as are some crystalline formations and such phenomena 
as tree roots, tree branches, coasts, lightning stnkes. shatter zones, 
information nets, and so on. 


Looking down on a bare winter-deciduous tree, we 
see a typical fractal, which we can also find in the 
fulgurites (sand fused by lightning) in sand dunes, and 
in the shatter zones of explosions. Tree roots are, in 
fact, a slow shatter or explosion underground. One 
way to plant an apple tree in very hard ground is to 
detonate a small plug of gelignite a foot or two below 
the surface; the roots will follow the shatter pattern, 
and further elaborate it. 

Scatters of objects may at first seem to present a class 
of events unrelated to either flow models or frac-tals, 
but fractals are being used to describe the scatters of 
tree clumps in grassland, or lichen on a stone. In a 
sense, the surface of spheroids created by branched 
phenomena (like the plan view of a tree crown) may 
show such apparently random scatters as growth 
points; or a curved section through the cut or pruned 
branches below the crown of a tree would also appear 
to be a scatter of points (Figure 4.1.E). These can be 
measured by fractal analysis. 

Fractal theory may give us a way to measure, 
compute, and design for branched or scattered 
phenomena, but we also need to understand the 
physical advantages of developing ever smaller 
conduits. Vogel (1981) gives many insights into this 
process and its effects. Large conduits are of use in 
mass transport, but both the laminar flow patterns 
within them and the fact that they have a small surface 
area relative to their volume makes them inefficient for 
the diffusion of materials or the conduction of heat 
across their walls. 

Ever smaller conduits have different qualities: flow is 
slow, almost viscous in very small tubes or branches; 
direction changes in small branches are therefore 
possible without incurring turbulence or energy losses. 
Walls can be permeable, and efficient collection, 
exchange, and transfer is effected (whether of materials 
or physical properties such as heat and light). Many 
small conduits efficiently interpenetrate the exchange 

Wherever there is a need to collect or distribute 
materials, or to trade both ways with media, branching 
is an effective response. In design, therefore, we need 
to use "many paths” in such situations as home 
gardens, where we are always trading nutrients as our 
main activity. There is little advantage in forming these 
paths as straight lines (speed is not of the essence), but 
rather in developing a set of cul de sacs or 
keyhole-shaped beds (this is also the shape of sacs in 
lungs). Convoluted paths in gardens have the same 
effect. They either bring the gardener into better 
contact with the garden, enabling collection and 
servicing to occur, or create better mutual exchange 
between the species in the garden. 

The high-pressure/low-flow nature of minor 
branches demands a very large total cross-sectional 
area of these in relation to the main supply arteries. 
Such small conduits may develop areas which in sum 
are 300-1,600 times that of the supply artery (our main 
roads are therefore much less in area than the foot 

tracks that lead off them). As an applied strategy, 
multiple small paths enhance our access to food 
systems, or in fact any system where we both take and 
give materials. 

In organisms, the multiple branches give the being a 
chance to recover from injury, preserve information, 
and permit regrowth in the event of minor damage. It 
is a fool-proof system of interchange. Another way to 
effect interchange is to elaborate on the walls of larger 
conduits by involutions, attached fins, irregular 
surfaces, or to create spirals in fluids or gases by 
bending or spiralling the conduits themselves, and in 
general inducing a larger surface of contact between 
the material transported and the media with which we 
wish to exchange nutrients, heat, or gases. 

Branching in trees is as often a result of external 
forces (wind and salt pruning, secateurs, or insect 
attack) as it is a result of internal cell patterns; it is as 
much forced upon things as it is the "best thing to do.” 
We must therefore see the branched form as an 
interaction between an organism or process, the 
purpose it serves, and the external forces of the media 
in which the organism is immersed (the forces acting 
on it externally to deform the perfect pattern). 

Along the streamlines (S1-S9 of our model Figure 
4.1), fluids and gases may pass in conduits or along 
"transmission cords”, food and signals are relayed to 
cells, and gases exchanged. Organs served by or 
serving these systems are half-models of our tree 
(kidneys, lungs) or branching fractals (mesenteries). 

No matter how long or complex conduits are, in the 
end their contents diverge, escape, and disperse, and at 
the intake materials are gathered from dispersed 
sources. It is this gathering and dispersal from both 

FIGURE 4.23 

Any torm specialised tor diffusion or infusion (lungs, kidneys, 
mushrooms, palm trees) is usually subject to branching, and develops 
a 'half-model' in one medium. The alvioli ot the lungs further 
resemble the 'keyhole beds' of a well-designed garden. 


-nd* or margins of events that is a basic function of the 
tree-like forms that pervade living natural systems and 
such phenomena as rivers or lava flows. 

_4 1 16_ 


Streams take up many ground patterns depending on 
the processes that have formed the underlying land¬ 
scape (block faulting, folding, volcanism) and the 
erosion and permeability characteristics of the 
underlying rock itself (limestone, mudstone, 
sandstone, clay). That is. the ultimate pattern of a 
stream network in landscape depends on process and 
substrate ; or we could call these process and media in 
terms of our model. 

We can easily see that stream patterns are the sum of 
preceding events that gave rise to the geological 
processes and rock types, so that streams have a lot to 
tell us about such processes, a skill learnt in photo 
interpretation. Figure 4.24 demonstrates some of the 
information so clearly told by stream patterns alone. 

However, if we abstract a fairly normal dendritic 
(tree-like) stream branching pattern as in Figure 4.25, 
we can find out these things from the pattern alone: 

• The ORDER of channels; the volume, or SIZE, of 

• The NUMBER OF BRANCHES in each order. 

• The TOTAL CHANNEL LENGTH in each order. 

• The MEANDER FREQUENCES in each order, or 
the behaviour of flow in the orders of branches. 

Streams usually have from one to seven orders, 
depending on their age, size, or gradient (fall over 

distance). An easy gradient develops as streams cut 
back their headwaters and fill in (aggrade) their lower 
reaches; meanders increase, and the velocity of flow 
decreases. These older streams, like a mature tree, have 
developed all their branches (as has an old company or 
an old army). Unless stream conditions themselves 
change (by a process of stream capture, an increase in 
rainfall, or a change in landscape), streams (and 
businesses) maintain an equilibrium of order. Looking 
at our dendritic, peaceful stream, we may find 
something as can be seen in Table 4.1. 

As the branches join up to make ever larger orders of 
channels, then about 3 times as many smaller branches 
join up to make each larger group, and so on. 
However, the individual lengths (of any one branch in 
each order) increase by 2 times as the order increases 
from 1-6. This is a very general rule of stream 
branching, even in non-dendritic patterns, and holds 
true for many streams. Similarly, meanders or bends 
also occur in a predictable way depending on the 
volume and gradient (flow). Regular meanders depend 
on certain velocities and stream width (as do stability 
of Von Karman vortex trails; Figure 4.14). The ratio for 
meanders or trails is about 1:3.6 (Vogel, 1981). 

Such regularity in branching may remind us of 
PULSERS (wave fronts), and indeed as each siz.e order 
changes, so does the behaviour not only of the water 
flow, but of its associated flora and fauna and their 
shapes. In the rills and runnels, streamlines and 
turbulent flow is observed. High in the stream 
gradients (the flattened S-curve of the stream bed in 
profile) we find insects and fish with suctorial parts 
able to stick on rocks, flattened fins to press them into 
the stream bed, flattened bodies and very streamlined 
profile In the middle orders, we get less turbulent 
water flow, more spiralling, less oxygenation, and more 

FIGURE 4.24 


Although the plan patterns ot rivers are often deemed by the physical comparable to the dendritic pattern, 
structures of landscape, the orders ot size and branches are 


free-swimming but very active fish of high oxygen 
demand; these may not live in the still water of higher 
order streams and low oxygen levels. Thus, we see that 
gaseous exchange is affected by turbulent flow, and 
that this in turn determines the life forms in these areas 
(Vogel, 1981). 

In the lower stream or estuaries, we get weak 
swimmers, less streamlined shapes, flat fish such as 
flounders, bulky molluscs, jellyfish in quiet areas and 
lower oxygen levels. We can list many of these life 
changes which are coincidental with changes in stream 
order, so we see that the order of streams is very much 
connected to the behaviour of the water, the landscape, 
and the shape of life forms in the watershed. Branching 
of pathways therefore changes species, behaviour, flow, 
and rates of exchange of nutrients or materials carried 
by the stream. When we examine a tree, we find that 
birds and insects are also confined to, or modified to 
suit, the orders of branching. 

_ 4^17 _ 


It is in the order of branching (as in our river) that we 
can gain insight into the order of orders, and the 
functions of orders. At each point of branching (or size 
and volume change) everything else changes, from 
pressures, flows, velocities, and gaseous exchange, to 
the life forms that associate with the specific size of 

TABLE 4.1: 








Folk Name 


Number of 

Ratio of 

A. Length 

Ratio of 






In the Order 



Sheet Flow 







x 3.5 


x 2.0 




x 3.3 


x 2.0 




x 3.3 


x 2.3 




x 2.7 


x 2.2 




x 3.0 






Average _ (*=3.0) _ (*2.0) 

(Modified after Tweadie, Water and the World, Thomas Nelson. Australia. 1975.) 

(Arrows indicate ascending orders by factor of increase) 

FIGURE 4.25 

A regular tree' based on the proportion of real nvers. The ogrves. or 
curved lines, can be viewd as pulses of growth, waves approaching 
the viscous ‘shoreline' of the leaves or (in the case of rivers) the slow 
seepage of upland rills Here, seven orders of branches exist: more 
orders become difficult to develop towards the diffusion surface, 
where viscous flow slows the movement of fluids 


branches. This is how we make sense of the fish species 
in streams, and the bird species in a tree. Each has its 
place in a set or order of branches, on the bark of 
stems, or the leaf laminae of the tree. 

This order, or size-function change, produces 
physical, social, and organic series. Not only species 
change with order, but so does behaviour. We cannot 
get a riot of one person, and fewer than 15 rarely clap 
to applaud as an audience. When we therefore come to 
construct hierarchies, the rules of order should guide 

An array of orders is observed in a wide range of 
phenomena such as human settlement size, numbers in 
social hierarchies, trophic levels (food pyramids), and 
the size of animals in allied zoological families. The 
size of the factor itself (times 3 for river branches) 
changes with the dimensions of the system (times 10 
for trophic pyramids). Physical entities from protons to 
universes display such order, with a consequent 
increase in the ratio, dimensions, and behaviours 
associated with size change (giant and dwarf stars 
behave very differently). 

As designers, we need to study and apply branching 
patterns to roads or trails, and to be aware of the stable 
orders of such things as human settlements, or we may 
be in conflict both with orderly flow (can we increase 
the size of a highway and not alter all roads?), with 
settlement size (villages are conservative at about the 
1000 -people order, and unstable much below or above 
that number), with sequences of dam spillways, and 
even with the numbers of people admitted to 
functional hierarchies where information is passed in 
both directions. We can build appropriate or 
inappropriate systems by choosing particular orders, 
but we do better to study and apply appropriate and 
stable size and factor classes for specific constructs. For 
example, in designing a village, we should study the 
orders of size of settlements, and choose one of these. 
This decides the number and types of services and the 
occupations needed, which in turn decides the space 
and types of shops and offices for a village of that size, 
and the access network needed. 

In human systems, we have confused the order of 
hierarchical function with status and power, as though 
a tree stem were less important than the leaves in total. 
We have made "higher" mean desirable, as though the 
fingers were less to be desired than the palm of the 
hand. What we should recognise is that each part 
needs the other, and that none functions without the 
others. When we remove a dominant animal from a 
behavioural hierarchy, another is created from lower 
orders. When we remove subordinates, others are 
created from within the dominants. So it is with 

Thus, we can see how rivers change their whole 
regime if we alter one aspect. We should also see that 
water is of the whole, not to be thought of in terms of its 
parts. Thus we refute the concept of sfflfws and assert 
that of function. It is not what you are; it is what you do 
in relation to the society you choose to live in. We need 

each other, and it is a reciprocal need wherever we 
have a function in relation to each other. 



All events are susceptible to classification over a 
variety of characteristics, and as, for example, clouds 
and galaxies have their pattern-names, so do many 
other phenomena. Some basic ways to classify events 
in a unified system are: 


Al. Explosive, disintegration, erosion, impact, 

A2. Growth, integration, construction, translation. 

A3. Conceptual, idea, creative thought, insight. 


Bl. Potential only (ungerminated seed, unexplored 
idea, unexploded bomb). 

B2. In process of evolution. 

B3. Completed (growth and expansion ceased), 

B4. Decaying (disintegrative, replaced or invaded by 
new events) disarticulated. 


Cl. One (linear phenomena), curves. 

C2. Two (surface phenomena), tessellae, dendrites. 
C3. Three (solid phenomena), trees. 

C4. Four (moving solid phenomena), includes the 
time dimension. 

C5. More (conceptual phenomena) models of 
particles or forces, states of energy. 


Dl. Generating across equi-potential surfaces 
(storms at sea). 

D2. Within media (weather "frontal" systems). 

D3. Throug h surfaces at 90° or so (trees). 

D4. En globements (some explosions and organisms). 
D5. An idea, located out of normal dimensions of 

By extending and applying these categories, all 
events can be given short annotations, e.g.: 

• A sapling is: A2, B2, C3, D3. 

• A falling bomb is: Al, Bl, C4, D2. 

_ 4^19 _ 


As we see the seed as the origin of the tree, so we can 
broaden our view, and our dimensions, and view the 
tree as the current time-focus of its own genealogy. 


Before it in time lie its ancestors, and after it its 
progeny. It lies on the plane between past and future, 
and (like the seed) determines by its expression the 
forms of both, and is in turn determined by them. Just 
as the stem of the tree now encapsulates its history as 
smaller and smaller growth rings, so universal time 
encapsulates the tree in its own evolutionary history. 
This is difficult to portray, and has more dimensions 
that we can illustrate on a page. It is the basis of the 
Buddhist belief that all time is enfolded or implicate in 
the present, and that current events are part of a total 
sequence, all of which are enfolded in the present tree 
as ancestors, or siblings. 

As we read this, we stand in the plane of the present; 
we are the sum of all our ancestors, and the origin of 
all our descendants. In terms of our model, we are at 
an ever-changing origin, located on the boundary of 
past and future. As well, we are spinning with the 
earth, spiralling with the galaxy, and expanding or 
contracting with the universe. As origins, we are on the 
move in time and space, and all these movements have 
a characteristic pulse rate. 

Our bodies contain the potential for future 
generations, awaiting the events of pairing to create 
their own future events. Like a seed origin buried in 
the tree stem, we are buried in the stem of our siblings 
in a genealogy, whose branches thrive, die, and put 
forth new shoots and roots over time. 

This is the case with all origins; they can all, even if 
ancient, be located in this matrix. If we know how to 
reconstruct the tree, we can find the place of the seed 
and vice versa. All rivers, erosion cells, and all glaciers 
originated, therefore, at the central stem of their 
courses, and built their pattern both ways along the 
kinetic gradient of their flow. Thus, in terms of the time 
dimension we see the present as the ORIGIN of both 
the past and the future (located as it is in the centre of 
our pattern). 

Designers can move sideways in the waves of time 
(as a surfer on a wave-front), transporting seed from 
continent to continent, permitting natural or induced 
hybrid palms and legumes to weave an alternative 
future. Mankind is an active translator of life, and, of 
course, of death. 

In all core models, including our own genealogy, the 
point where all the important action takes place is 
through the point of origin, which is always in the 
present. How we behave now may determine not only 
the future, but the past (and all time). Think of that, 
and realise that you are really where it’s at, no matter 
when you are! I find great personal meaning in the 
Australian aboriginal life ethic, and little enough 
comfort in any pie-in-the-sky. If it is my actions which 
determine the sky, 1 want it to be full of life, and I 
choose to believe that I am part of all that action, with 
my own job to do in this life form, and other jobs to do 
in other phases. 

_ 120 _ 


I live in the crater of an ancient volcano, the caldera of 
which is in part eroded by the sea. Trees rise from the 
soils, and birds nest in them. From the seeds and eggs 
in the trees arise new life forms. Great wind spirals 
sweep in from the west with almost weekly regularity, 
bearing the fractal forms of turbulent clouds and 
causing, in autumn and mid-summer, lightning and 

On this peninsula, the terminal volcanic core stands 
fast, refracting waves to either side, and creating a 
pinched neck of sand which joins us to the mainland. 
The hills are stepped by successive sea-level changes, 
and record the pulses of long-term cycles and success¬ 
ions. Day follows night, and life follows death follows 

All of these phenomena are a unity of patterns long 
repeated and based on one master pattern, each one 
preparing for new evolutions and dissolutions. It is the 
number and complexity of such cycles that give us life 
opportunities, and life is the only integrative force in 
this part of the universe. Let us respect and preserve it. 

An understanding (even a partial understanding) of 
the underlying patterns that link all phenomena cre¬ 
ates a powerful abstract tool for designers. At any 
point in the design process, appropriate patterning can 
assist the achievement of a sustainable yield from 
flows, growth forms, or information flux. Patterns 
imposed on constructs in domestic or village assemb¬ 
lies can result in energy savings, and satisfactory 
aesthetics and function, while sustaining those 
organisms inhabiting the designed habitat. 

Patterning is the way we frame our designs, the 
template into which we fit the information, entities, 
and objects assembled from observation, map overlays, 
the analytic divination of connections, and the selec¬ 
tion of specific materials and technologies. It is this 
patterning that permits our elements to flow and 
function in beneficial relationships. The pattern is 
design, and design is the subject of permaculture. 

Bohm (1980) urges us to go beyond regarding our¬ 
selves as interactive with each other and the en¬ 
vironment, and to see all things as "projections of a 
single totality". As we experience this totality, 
incorporate new information, and develop our con¬ 
sciousness, we ourselves are fundamentally changed. 
To fail to take this into account must inevitably lead 
one to a serious and sustained confusion in all that one 
does." The word "implicate” in the title of Bohm’s work 
comes from the Latin "enfolded", and when we 
separate individuals, effects, or disciplines from this 
enfolded order, we must recognise only that we have 
part of the unknowable totality, not the truth itself. 
There are no opposites, just phases of the one 

For myself, and possibly for you if you take up the 
study of patterns, the contemplation of the forms of life 


and flow has enabled me to bring to consciousness the 
unity of all things, and the enfolded nature of Nature. 
In the matter of genealogy we can become conscious of 
ourselves in the time and pattern stream, and it is 
startling to realise that (as origin) we "determine", or 
rather define and are defined by, our ancestry as much 
as we define and are defined by our descent. We do not 
doubt our physical connection to either ancestry or 
descent. It is the sense of "all are present here" that is 
revealed by pattern: to be encapsulated in, and a 
pervading part of, a personal genealogical pattern 
which is itself a result of a pattern of innumerable 

Patterns tell us that all is streams, all particles, all 
waves. Each defines the other. It tells us that all is one 
plan. Although we find it difficult to see pattern in all 
the plan, it is there. We are the universe attempting to 
define its processes. A Kalahari bushman would say 
we are the dreams of a dreamer. What I feel we can 
never define is substance (except as process; this is all it 
may be). We can only know a few local patterns, and 
thus have some weak predictive capacity. It is the 
pattern that our local patterns cannot know that will 
surprise us, the strike of cosmic lightning from an 
unguessed source or stress. 

Finally, pattern understanding can only contribute to 
the current and continuing evolution of new world 
views based on the essential one-ness of all 
phenomena. Lovelock (1979) has perhaps best 
expressed that combination of scientific insights and 
older tribal beliefs which assert the interdependence of 
animate and inanimate events. The universe, and this 
earth, behave as self-regulating and self- generated 
constructs, very much akin to a single organism or a 
thought process. 

The conditions which make life possible are balanced 
about such fine tolerances that it seems close to 
certainty that many processes exist just to preserve this 
equilibrium in its dynamic stability. 

From the point of view of biologists, Birch and 
Cobb’s The Liberation of Life (1984; see a review by 
Warwick Fox in The Ecologist 14(4)1 denies the validity 
of the existence of individual organisms or separate 
events; all exist in a field of such events or as an 
expression of one life force. Organisms such as 

ourselves exist only as an inseparable part of our event 
environments, and are in continual process of exchange 
with the animate and inanimate entities that surround 
us. We are acted upon and acting, created and creating, 
shaped and shaping. Fox asserts, as I have here, that 
“we must view the cosmos as an infinite complex of 
interrelated events"; all things "are in actuality 
enduring societies of events." 

Theoretical physicists (Capra, 1976) contribute to 
such world views, all of which are in conflict with the 
current ethics that govern political, educational, and 
economic systems, but all of which are contributing to 
an increasing effort to unify and cooperate in a 
common ethic of earth-care, without which we have no 
meaning to the universe. 

_ ^21 _ 


There are two aspects to patterning: the perception of 
the patterns that already exist and how these function, 
and the imposition of pattern on sites in order to 
achieve specific ends. Both are skills of sophisticated 
design, and may result in specific strategies, the 
harmonious resolution of problems, or work to 
produce a local resource. Given that we have absorbed 
some of the information inherent in the general pattern 
model, we ne?d some examples of how such 
patterning has been applied in real-life situations. 

A bird’s-eye view of centralised and disempowered 
societies will reveal a strictly rectilinear network of 
streets, farms, and property boundaries. It is as though 
we have patterned the earth to suit our survey 
instruments rather than to serve human or 
environmental needs. We cannot perhaps blame Euclid 
for this, but we can blame his followers. The 
straight-line patterns that result prevent most sensible 
landscape planning strategies and result in neither an 
aesthetically nor functionally satisfactory landscape or 
streetscape. Once established, then entered into a body 
of law, such inane (or insane) patterning is stubbornly 
defended. But it is created by, and can be dismantled 


MT of 

A h k £ A 

i^pSKf 7 l J 

v tPgjjgBL • 

PoR. ' Jr 

Meteor impact crater or 'drip splash' forms resemble volcanic 

Percussion and pressure flaking produce typical patterns in obsidian 
or chert tools shaped by stone workers 


by, people. 

A far more sensible approach was developed by 
Hawaiian villagers, who took natural ridgelines as 
their boundaries. As the area was contained in one 
water catchment, they thus achieved very stable and 
resource-rich landscapes reaching from dense 
cloud-forests to the outer reefs of their islands. The 
nature of conic and radial volcanic landscapes with 
their radial water lines suits such a method of land 
division. It is also possible for a whole valley of people 
to maintain a clean catchment, store and divert 
mid-slope water resources for their needs, catch any 
lost nutrients in shallow ocean enclosures (converting 
first to algae, then to crabs and fish), and thus to 
preserve the offshore reef area and the marine 
environment. Zulus and American Indians adopt the 

circular or zonal modes in their plains settlements. 

Such models can be studied and adopted by future 
(bioregional) societies as sane and caring people 
become the majority in their region, and set about the 
task of landscape rehabilitation. Sensible land division 
is a long-delayed but essential precursor to a stable 

_ ±22 _ 


As I travel about the world, I find tribal peoples using 
an enormous variety of traditional patterns. These 
decorate weapons, houses, skin, and woven textiles or 

songs tor specific search patterns, and an assistant judges solar and 
star elevations (latitude) via a water level 

• At nioht . the glow ot lite forms in deep sea trenches is awaited (the 
'lightning' from the deeps’), bird song and echoes trom headlands are 
listened for. and the phosphorescent glow of the forests ashore is 

• An experienced man lowers his testicular sac into the sea to 
accurately guage water mass temperature. 

• The wind carries a variety ot scents from forests, rock lichen, bird 
colonies, and fish schools: all are recorded 

• A net catches indicator organisms related to the water mass, and 
near shores a 'lead line’, or depth line, is used to find banks and 
sample bottom fauna picked up in soft grease. 

• A crystal ot calcite may be used to predict ram or to find the sun on 
overcast days by polarisation of light—the lodestone* of navigators 

FIGURE 4.26 


• The helmsman Sings to time the log line, and feels for current 
deflections through his steering oar. He or she sings to record the 
stages ot the journey and the ’rivers’ (currents) of the sea. 

• Lookouts note star patterns, bird flight, cloud trains, or light re¬ 
fracted trom coastal lagoons. Water speed is recorded by a knotted 
float line. 

• A skilled listener in a ’black box’ near the keel listens to wave 
refraction trom the hull, predicts storms or islands from wave periods 
timed by chants. 

• A nayiaalQr consults a voyage ’chart’ of sticks and cowries 
representing the interaction of phenomena and sings the navigation 


baskets. Many patterns have sophisticated meaning, 
and almost all have a series of songs or chants 
associated with them. Tribal art, including the forms of 
Celtic and ancient engraving have a pattern complexity 
that may have had important meanings to their 
peoples. We may call such people illiterate only if we 
ignore their patterns, songs and dances as a valid 
literature and as an accurate recording system. 

Having evolved number and alphabetical symbols, 
we have abandoned pattern learning and recording in 
our education. I believe this to be a gross error, because 
simple patterns link so many phenomena that the 
learning of even one significant pattern, such as the 
model elaborated on in this chapter, is very like 
learning an underlying principle, which is always 
applicable to specific data and situations. 

The Maori of New Zealand use tattoo and carved 
patterns to record and recall genealogical and saga 
information. Polynesians used pattern maps, which 
lacked scale, cartographic details, and trigonometric 
measures, but nevertheless sufficed to find 200-2,000 
island specks in the vastness of the Pacific! Such maps 
are linked to star sets and ocean currents, and indicate 
wave interference patterns; they are made of sticks, 
flexed strips, cowries, and song cycles (Figure 4.26). 

Pitjantjatjara people of Australia sing over sand 
patterns (Figure 4.27), and are able to "sing" strangers 
to a single stone in an apparently featureless desert. 
Many of their designs accurately reflect the lobular 
shapes and elaborate micro-elevations of the desert, 
which are nevertheless richly embroidered by changes 
in vegetation, and are richly portrayed in what (to 
Westerners) appears as abstract art. Some pattern 
mosaics are that of fire, pollen, or the flowering stages 
of a single plant, others are of rain tracks and cloud 
streets, and yet others involve hunting, saga, or 
climatic data. 

Children of many tribes are taught hundreds of 
simple chants, the words of which hide deeper, 
secondary meanings about medicinal, sacred, or 
navigational knowledge. All this becomes meaningful 
when the initiate is given the decoding system, or finds 
it by personal revelation (intuition). A pattern map 
may have little meaning without its song keys to 
unlock that meaning. Initiation can also unlock 
mnemonic patterns for those who have a first clue as to 

Dances, involving muscular learning and memory, 
coupled with chants, can carry accurate long-term 
messages, saga details, and planting knowledge. Many 
dances and chants are in fact evolved from work and 
travel movements. Even more interesting are the 
dance-imitations of other animal species, which in fact 
interpret for people the postural meanings of these 
species, although in a non-verbal and univers- 
ally-transmittable way. We may scarcely be aware that 
many of our formal attitudes of prayer and submission 
are basic initiations of primate postures, for the most 
part taken from other species. Even the chair enables 
us (as it did the Egyptians) to maintain the postures of 

FIGURE 4. 27 


A sono map ol the Pitjitjantjara women Such forms closely resemble 
desert claypans if the long axis is regarded as a How axis, and the 
zones as lobular vegetation. 

baboons, and baboons were revered as gods and 
embalmed by the Egyptian chair-makers. We can 
remember hundreds of songs, postures, and chants, but 
little of prose and even less of tabulated data. 

Anne Cameron (Daughters of Copper Woman, 
Vancouver Press, 1981) writes of song navigation in the 
Nootka Indians of British Columbia: There was a song 
for goiri to China, and a song for goiri to Japan, a song 
for the big island and a song for the smaller one. All 
she (the navigator) had to know was the song and she 
knew where she was..." 

The navigation songs of the women on canoe 
voyages record "the streams and creeks of the sea' —the 
ocean currents, headlands and bays, star constellations, 
and “ceremonies of ecstatic revelation". From California 
to the Aleutians, the sea currents were fairly constant 
in both speed and direction, and assisted the canoes. 
The steerswomen used the (very accurate) rhythm of 
the song duration to time both the current speed and 
the boat speed through the water. Current speed would 
be (I presume) timed between headlands, and boat 
speed against a log or float in the water. The song 
duration was, in fact, an accurate timing mechanism, 
as it can be for any of us today. 

Song stanzas are highly accurate timers, accurate 
over quite long periods of time, and of course re¬ 
producible at any time. The song content was a record 
of the observations from prior voyages, and no doubt 
was open to receive new data. 

People who can call the deer (Paiute wise men), the 
dolphin (Gilbert Islanders), the kangaroo (tribal 
Tasmanians) and other species to come and present 
themselves for death had profound behavioural, 
interspecific, "pulser" pattern-understanding. Just as 
the Eskimo navigated, in fog, by listening to the quail 


dialects specific to certain headlands, we can achieve 
similar insights if our ear for bird dialect is trained, so 
that song and postural signals from other species make 
a rich encyclopaedia of a world that is unnoticed by 
those who lack pattern knowledge. People who can kill 
by inducing fibrillation in heart nerves have a practical 
insight into pulser stress induction; many tribespeople 
can induce such behaviour in other animal species, or 
in people (voodoo or ' singing"). 

The attempts of tribal shamans to foresee the future 
and to control dreams or visions by sensory depriva¬ 
tion, to read fortunes by smoke, entrails, water, or the 
movement of serpents, or to study random scatters of 
bones or pebbles are not more peculiar than our efforts 
to do the same by the study of the distribution of 
groups of measures or the writhing of lines on 
computer screens. By subjecting ourselves to isolation, 
danger, and stress, we may pass across the folds of 
time and scan present and future while we maintain 
these "absent" states, as described by Dunn (1921) in 
his Experiment with Time , and as related by participants 
in the sun dances of the Shoshone nation. As we 
drown, or fall from cliffs, our lives "pass before our 
eyes" (we can see the past and future). 

We need to think more on these older ways of 
imparting useful or traditional information, and of 
keeping account of phenomena so that they are 
available to all people. Number and alphabet alone will 
not do this. Pattern, song, and dance may be of great 
assistance to our education, and of great relevance to 
our life; they are the easiest of things to accurately 

Apparently simple patterns may encode complex 
information. There may be no better example than that 
of the Anasazi spiral, with 19 intercepts on its "horizon" 
"horizon" line (Figure 4.28). This apparently simple 
spiral form is inscribed on a rock surface near the top 
of a mesa in desert country in the southwest USA. 
Three rock slabs have been carefully balanced and 
shaped, as gnomons which cast moon-shadows or (by 
their curvature) direct vertical daggers of sunlight to 
the points of the spiral. The 19 points at which the 
spiral intersects the horizontal axis are those at which 
the shadow of the moon is cast by a gnomon on the 
spiral, and indicate the moon elevation or 19-year 
(actually 18 . 6 ) cycle caused by the sway of the earth s 

Thus, one simple spiral records lunar and solar 
cycles for the regulation of planting, the timing of 
ceremonies, and (as modem science has just realised), 
the prediction of the 19-year (18.6 year) cycle of 
drought and flood. A very simple pattern encodement 
thus represents a practical long-term calendar for all 
people who live nearby. The Anasazi culture is extinct, 
and only a persistent investigation by Anna Soaer (an 
artist with intuitive observational skills) has revealed 
the significance of this arrangement. Scientists have 
often doubted the capacity of tribal peoples to pattern 
such long-term and complex events, which in terms of 
our clumsy alphabetical and numerical symbols are not 

FIGURE 4.28 

A pefrogfyph (rock carving) ol the Anastasi Indians (North America) 
forms a long-term calendar of sun and moon cycles. 

only forgettable, but would take a small library to 
encode. The knowledge so presented is available to 
very few (ABC TV Science programme, Australia, 20th 
January '84). However, wherever tribes remain intact, 
there are many such sophisticated pattern-meanings 
still intact, all as complex and information-dense. 

In the complex of time-concepts evolved by 
Australian Aborigines, only one (and the least 
important) is the linear concept that we use to govern 
our life and time. Of far greater everyday use was 
phenomenological (or phenological) time; the time as 
given not by clocks, but by the life-phenomena of 
flowers, birds, and weather. An example from real life 
is that of an old Pitjatjantjara woman who pointed out 
a small desert flower coming into bloom. She told me 
that the dingoes, in the ranges of hills far to the north, 
were now rearing pups, and that it was time for their 
group to leave for the hills to collect these pups. 
Thousands of such relationships are known to tribal 
peoples. Some such signals may not occur in 100 or 500 
years (like the flowering of a bamboo), but when it 
does occur, special actions and ceremonies are 
indicated, and linked phenomena are known. 

Finally, in tribal society, one is not wise by years, but 
by degree of revelation. Those who understand and 


Full moon SHAPow AT >1inimum' Full moon shapow AT 
Point CAST *Y 3*°SlAB ' Maximum'R ttWG PONT 


embody advanced knowledge are the most intuitive, 
and therefore most entitled to special veneration. Such 
knowledge is almost invariably based on pattern 
understanding, and is independent of sex or even age, 
so that one is "aged" by degree of revelation, not time 
spent in living (there are some very unrevealed "elders" 
in the world!). 

_ ^23 _ 


Buddhists remind themselves of the pattern of events 
with their oft-repeated chant "Om mani pad me hum”; 
pronounced "Aum ma-ni pay-may hung" by Tibetans 
and Nepalese, and meaning: 

Om: the jewel in the lotus : hum 

om • ma • nl • pay • may • hung 

As Peter Matthiessen explains it (The Snow Leopard. 
Picador, 1980): 

Aum (signing on) is the awakening or beginning 
harmonic, the sound of all stillness and the sounds of 
all time; it is the fundamental harmonic that recalls to 
us the universe itself. 

Ma-ni: The unchanging essence or diamantine core 
of all phenomena; the truth, represented as a dia¬ 
mond, jewel, or thunderbolt. It is sometimes repre¬ 
sented in paintings as a blue orb or a radiant jewel, and 
sometimes as a source of lightning or fire. 

Pay-may: "Enfolded in the heart of the lotus" (mani 
enfolded). The visible and everyday unfolding of 
events, petals, or patterns thus revealing the essential 
unchanged core (mani) to our understanding. The core 
itself, or the realisation of it, is nirvana (the ideal state 
of Buddhism). The lotus represents the implicate order 
of tessellated and annidated events, and the process of 
unfolding the passage of time to successive revelations. 
At the core is unchanging understanding. 

Hung (signing off): "It is here, now." A declamation 
of belief of the chanter in the words. It also prefaces the 
"Om" or beginning of the new chant cycle, although in 
a long sequence of such short chants, all words follow 
their predecessors. This is the reminder mnemonic of 
implicate time; all events are present now, and forever 
repeated in their form. 

DORJE, or Dorje-chang, is the Tibetan Buddha- 
figure who holds the dorje (thunderbolt), represented 
as a radiant stone which symbolises cosmic energy. 
Dorje is "the primordial Buddha of Tibet", who began 
the great succession of current and past reincarnations. 
His colour is blue, for eternity, and he may carry a bell 
to signify the voiceless wisdom of the inanimate, or the 
sound of the void. 

Dorje is an alter ego of Thor of the Norsemen, Durga 
of the Hindu, and of thunderbolts and "thunderers” of 
other tribal peoples. The mani or stone of Thor was 
Mjollnir, his hammer, from which derives Mjoll- 
nirstaun, and (eventually) Mollison (by way of 
invasions into Scotland, and migrations). Thus, even 
our own names may remind us of the essential oneness 
of the events and beliefs around us. 

We can choose from tribal chants, arts, and folk 
decoration many such mnemonic patterns, which in 
their evolution over the ages express very much the 
same world concept as does modern physics and 
biology. Such thoughtful and vivid beliefs come close 
to realising the actual nature of the observed events 
around us, and are derived from a contemplation of 
such events, indicating a way of life and a philo-sophy 
rather than a dogma or set of measures. 

Beliefs so evolved precede, and transcend, the 
emphasis on the individual, or the division of life into 
disciplines and categories. When we search for the 
roots of belief, or more specifically meaning, we come 
again and again to the one-ness underlying science, 
word, song, art, and pattern: The jewel in the heart of 
the lotus". 

Thus we see that many world beliefs share an 


essential core, but we also see the drift from such 
nature-based and essentially universal systems 
towards personalised or humanoid gods, dogma, and 
fanaticism, and to symbols without meaning or use in 
our lives, or to our understanding of life. Many other 
world-concepts based on the analogies of rainbows, 
serpents, and song cycles relate to aspects of the 
integrated world view, and are found in Amerindian 
and Australian tribal cultures. 



We can pattern the behavior of human and other social 
animals to represent aspects of their society. A set of 
such patterns, derived from studies I and my students 
made in Tasmania from 1969 to 1974 are illustrated in 
Figure 4.29. The central pattern represents the orders 
or castes of occupational level (status) in its long axis. 
There are seldom more than seven major occupational 
levels even in such rigorously-stratified hierarchies as 
the army. The width of the Figure 4.29 represents the 
numbers of people at each level, and for this 
configuration we summed the numbers of people in 
several organisations (to sample some 35,000 people), 
including the local army, a multinational company, 
some churches and many small businesses. 

Within the general "boat" pattern form so evolved, 1 
have marked some arrows to represent genetic 
streaming (bv marriage or sexual congress); important 
classes of occupation are: 

Characteristics are a general dearth of material 
resources, low status, part-time occupations, and a 
remarkable preponderance of male births and survived 
male children (about 140 males per 100 females). Large 
families. Serial polyandry is common or acceptable. 


Adequate resources, nine-to-five jobs, some job tenure, 
and a "normar birth ratio of 104 males per 100 fe¬ 
males. Mixed white collar and skilled technical 
workers, average family sizes. Monogamy is an ideal, 
but is often expressed as serial monogamy. 


Few people, extensive resources, flexible and often 
self-set times, and a high proportion of female children 
(about 100 females to 70 males or less); urban 
professionals or managers would typify the group. 
Small families, effective polygyny via concubines or 


Executive directors and landed nobility. Variable 
family sizes but a preponderance of female children (as 
per 3. above), and a habit of lateral intermarriage for 
economic alliances, facilitated by exclusive schools and 

The imbalance of the sex ratios in these strata 
ensures a genetic turnover or diffusion between 
classes; a streaming of genetic materials between levels 
over generations. 



Art, in the forms of song, dance, and sculptural or 
painted objects, or designs, is an ancient preoccupation 
of all peoples. There is little doubt that most (if not all) 
tribal art is intended for quite specific ends; much of 


| Behaviour" 



ft Serial 



■\ EXCK6 £ BiRmS 





Exr^aye fhxse. 



Dress d'&tfrus 
wo 99 ) 

SvMf&l OfPtOPlf. 

FIGURE 4.29 


Ttie form of social hierachy based on occupational status. Note the 

over production of males (as a primary sex ratio) at the lower resource 

level, thus marital habits are based on resources and sex ratios. Width 

indicates number of people at each level (n = 35.000 Tasmania. 



tribal art is a public and ever-renewed mnemonic, or 
memory-aid. Apparently simple spiral or linear 
designs can combine thousands of bits of information 
in a single, deceptively simple pattern. The decorative 
function is incidental to the educational and therefore 
sacred information function in such patterns. "Decor¬ 
ation” is the trivial aspect of such art. 

Much of modern art is individualistic and 
decorative; some "motif art is plagiarised from ancient 
origins, but no longer has an educational or sacred 
function. Entertainment and decoration is a valid and 
important function of the arts, but it is a minor or 
incidental function. Social comment is a common art 
form in theatre and song, and spirited dances and 
songs are cheering or uplifting. But I know of no 
meaningful songs or patterns in my own "mono¬ 
culture", based as it is on the jingles of advertisements 
and purely decorative and trivial patterns of art, and 
on education divorced from relevant long-term 
observations of the natural world. 

The induction of moods and the record of ephemera 
are not the primary purposes of sacred or tribal art, 
which is carefully assembled to assist the folk records 
of the function and history of their society. Some 
modern sculptural forms, such as the "Flowform" 
systems of the Virbella Institute, Emerson College, 
Kent, UK (Figure 4.33) are modelled on older Roman 
water cascades, and serve both an aesthetic and a 
water-oxygenation function, assisting water 
purification. This is a small step towards applied art as 
patterning in everyday use, as are some engineering 
designs. We could well reintroduce or evolve pattern 
education, which gives ei'ery member of society access 
to profound concepts or specific knowledge. 

Art belongs to. and relates to, people. It is not a way 
to waste energy on resources for the few. Sacred calen¬ 
dars melted down to bullion or objets d art are a 
degradation of generations of human effort and know¬ 
ledge, and the sacred art of tribal peoples hidden in 
museum storerooms are a form of cultural genocide, 
removing knowledge from its context, and trivialising 
objects to decorations or loot. 

Human information, as a tribal art form, is most 
frequently debased and destroyed less for monetary 
gain than for the replacement of public information by 
an exotic, secretive, irrelevant and basically un¬ 
informed centralised belief system. The fanatic cares 
not what is destroyed if it empowers the repressive 
hierarchy that is then imposed. Most tribal art has been 
burnt, looted, destroyed, and broken by invading belief 
systems, destroyed by those seeking secret power 
rather than open knowledge, or by those who are 
merely destructive. Book-burning and image¬ 
breaking is the reaction of the alienated or intellectu¬ 
ally-deprived to the accumulated wisdom of its 
revelationary ancestors. We most damage ourselves 
when we destroy information and aids to under¬ 

It is a challenge to artists to study and portray 
knowledge in a compact, memorable, and trans¬ 

missible form, to research and recreate for common use 
those surviving art forms which still retain their 
meaning, and to re-integrate such art with science and 
with society and its functions and needs. It is a 
challenge to educators to revive the meaningful 
geometries, songs, and dances that gave us, and our 
work, meaning. 



A sophisticated application of pattern is found in the 
herb spiral (Figure 4.30) which I evolved in 1978 as a 
kitchen-door design. All the basic culinary herbs can 
be planted in an ascending spiral of earth on a 2 m 
wide base, ascending to 1 or 1.3 m high. All herbs 
planted on the spiral ramp are accessible. The construct 
itself gives variable aspects and drainage, with sunny 

■6.ECTlONiAU etevATioNi A A 

FIGURE 4. 30 

Pattern applied A modest 2 m diameter by 1 m high earth spiral 
accommodates all necessary culinary herbs close to the kitchen door 
and can be watered with one 2 m sprinkler—a considerable saving in 
space and water as the ramp and walls exceed 9 m ol plant space. 


dry sites for oil-rich herbs such as thyme, sage, and 
rosemary, and moist or shaded sites for green foliage 
herbs such as mint, parsley, chives, and coriander. 

This is a rare three-dimensional earth construct on a 
small scale, and compactly coils up a linear path or bed 
of herbs into one mound at the kitchen door, thus 
making the herbs accessible and convenient to the 
kitchen itself. If kitchens are not at ground level, roof or 
balcony gardens can carry pot-herbs in stepped walls, 
on wall shelves, in window boxes, or as stacks of pots 
in earth mounds. 

Pattern analyses can also be applied to water 
conservation. For example, a mulch-pit (60 cm wide 
and deep), surrounded by a planting shelf and spill 
bank totalling 1.2 m (4 feet) across has a 3.8 m (12 foot) 
perimeter, but can be efficiently watered with one 
low-pressure sprinkler, whereas a 3.8 m straight row 
takes three such sprinklers. 

Another advantage is the central (one-drop) mulch 
pit, so that the plants eventually overshade the centre 
to prevent evaporation. Such circle-mulch- grow pits 
are made 1.8 m (6 feet) across for bananas, and 1.8-3 m 
(6-10 feet) across for coconuts; all out- produce row 
crop for about one-third of the water use. A series or 
set of such gardens greatly reduce the path space and 
land area needed for home gardens, or orchards of 
banana and coconut (Figures 4.31 and 10.26). 

A field application of patterned ground designed to 
direct flow, and capture materials in flow, is that of 
flood-plain embankments or tree lines (poplar, willow, 
tamarack), or both combined. These are very effective 
pattern impositions on landscape (although all occur 
naturally as rock dykes or resistant rock strata in the 
field) that can have several beneficial effects for a 
household or settlement nearby (Figure 4.32). 

A more conscious and portable applied pattern set is 
that of the "Flowform" models being developed at the 
Virbella Institute by a small group of artist- 
technicians. Such turbulence basins are apparent in 
nature as shaped basins in streams flowing over 
massive sandstones or mudstone rocks. They are even 
in antiquity modelled in pozzelanic cement by Roman 
hydrologists. Flowforms are artificial replicates of the 
rock forms carved by turbulent streams, cast in 
concrete or fibreglass (Figure 4.33). 

Stacked in sets below sewage pipe outfalls or above 
fish ponds at pipe inlets, they efficiently mix air and 
water by inducing turbulence in flow. Three distinct 
mixing effects are noticeable; the first a plunge or 
vertical overturn as fluid drops from one basin to an¬ 
other; the second as a figure-8 or lateral flow around 
the basins themselves; and the third (a fascinating 
process) as an interaction between these two, as water 
coursing around the basins deflects the vertical drop 
flow and switches it from side to side in a regular 

Within these major turbulence patterns (so clearly 
portrayed by da Vinci (Popham, A.E., The Drawings of 
Leonardo da Vinci, Jonathan Cape, London, 1946) and 
further analysed in terms of computer models and 

catastrophic theory by Chappell (in: Landform 
Evolution in Australia, ANU Press, Canberra 1978) for 
coastal uprush and backwash turbulence) are distinct 
vortices and counterflow, overfolds and cusps that 
further mix air and water at the edges of the basins and 
in the main flow stream. 

Thus, artificial Flowform basins induce aeration, 
oxidise pollutants, and are themselves aesthetically 
pleasing and instructive hydrological pattern-models 
of naturally-occuring constructs. They have practical 
use in the primary treatment of sewage and organ¬ 
ically polluted waters, and in the oxygenation of ponds 
for aquatic species production. Models of this type are 
the result of a long evolution beginning with wonder, 
sketches, analysis, observations, and then proceeding 
via constructed hydrological basins to practical 
applications over a wide variety of sites. In nature and 
in the Flowform system, the basins can be elongate, 
truncate, symmetrical, asymmetical, stepped in line, 
stacked like ladders, or spiralled to conserve space. 

_ ^27 _ 


Alexander, Christopher et al, A Pattern Language, 
Oxford University Press, 1977. 

(Instances successful design strategies for towns, 

Bascom, Willard, Wanes and Beaches, Anchor Books, 
New York, 1980. 

FIGURE 4.31 


Here, a 4 m row of crop needs three 1 2 m sprinklers, while a circle of 
radius 0 6 m (4 m circumference) needs only one 1.2 m sprinkler, a 
saving of 60% in water use. Such systems apply onty on the small 
scale, where plants can shade the inner circle. 


'A Peaecrc>f^ me To 

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0?£H Ttif6£- can pe- 




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*, pep^Tfi) 

c Coixecro £ - veaecxov? of 

TZ£e£> T<? BRW6 MouO+ ( ««?ew>P 
At4P $IL.T To PlAfM 606£. 


\?Hmotep *a?h.£ 

f*X9je*£> -TV AU0UJ F**\ 
\ove*> *H\UOW<> ANP TO 

\Ae«ATe ^Am. at 

—\^OaJ ia/«T«5« 

J E,Oft'P$ OF WW 

off 3RU5W, To 
*/«* ANO W7VTB2. 
fACT- PUx?P C«op 

e.vftt »o 

FIGURE 4.32 


Floodwaters carry sill, mulch, and firewood and can be used to scour 
out river sand Here, several structures on a Hood plain gather 
materials or direct water energy to benetit production 


Birch, and Cobb,77jc Liberation of Life, Cambridge 
University Press, 1981. 

Bohm,W7io/i*»ifss and Implicate Order, Routledge and 
Kegan Paul, 1980. 

Capra, Fritz,77ic Tao of Physics, Fontana Press, 1976. 

Cook, Sir Theodore Andrea, The Curves of Life, 
Constable, London, 1914 (reprint) 

Escher, M. C. and J. L. Locher, The World ofM.C. Escher, 
Harrv N. Abrams Inc. New York, 1971. 

Goold, J. et alia. Harmonic Vibrations and Vibration 
Figures, Newton & Co. London, 1909. 

(see also: Model Engineer 3 May '51,8 Sep '60; Hobbies 
Nov 1966; and New Scientist 22/29 Dec '83). 

Illert, Christopher, Sea Shell Mathematics, 
self-published, 1984: 76Seaview Rd., West Beach, 
South Australia 5024. 

Lovelock, J. E .,Caia: A New Look at Life on Earth, Oxford 

University Press, 1979. 

Leapfrogs, Curves, Tarquin Pubs. Stradbroke, Diss, 

Norfolk, U.K., 1985. 

Mandelbrot, Benoit, The Fractal Geometry of Nature. 

W.H. Freeman Co. New York, 1982. 

(The basic book on fractals, computer graphics) 

Murchie, Greg, The Seven Mysteries of Life, 1984, 
self-published: Marlborough, NH, USA. 

Pearce, Peter, Structure in Nature as a Strategy for Design, 
M.I.T. Press, 1979. 

Schwenke, Theodore, Sensitive Chaos; the Creation of 
Flowing Forms in Air or Water, Schocken Books, N.Y., 


Thompson, D'arcy W., On Growth and Form, Cambridge 
University Press, 1952. 

(Multiple examples of forms in nature, spirals) 

^refpgp ft Kies of 

Ft6\+£. 5I6HT 
TURtt/ues/ce. ivt. 
oo-fffiu- PfcoM &ACW 

i&f-r To ri cut 

TU£ ctrotmE FU>6- /si H»t 
H£XT frrSisJ. (see ptATe). 


Tweedie, A. D., Water and the World, Thos. Nelson 
(Aust) Ltd., 1975. 

(On the order of stream flow and stream patterns) 

Virbela Institute, Emerson College, Forest Row, East 
Sussex RH18 5JX (Flowform designs and research, 

Vogel, Steven, Life in Moving Fluids ; the Physical Biology 
of Flow, Willard Grant Press, Boston, 1981. 

(A sensitive and scholarly study of life forms in flow) 

Weyl, Hermann, Symmetry, Princeton University Press, 
NJ, USA. 1983. 

New Scientist, New Science Publications, 
Commonwealth House, 1-19 New Oxford St. London 

5 Oct 78 
15 Nov ’84 
31 May ’84 
7 Jun ’84 

20 Mar 79 
14Jun 79 
5 May ’83 
26 Apr ’84 
5 May ’83 
17 Nov ’83 

21 Apr ‘77 
11 Oct '84 
4 Apr '85 

On pulsers and biological clocks 
On the gravity anomalies in the geoid 
The Robinson Congruence 
Recombination of DNA in a plus-torus 
The swirling of water 
The spiral classification of galaxies 
Symmetry, geometry, fractals 

Inversion and reflection of forms 

On impact craters 

The great tennis ball of earth" 

The pineal gland as a timepiece 
Fractals, pulsars, black holes 



Read in pattern analysis, and study the relationships of 
ORDERS and FORMS in nature. Patterned systems 
must be of appropriate size, or of the right order (i.e. 
note that small systems operate for things like frost 
protection and water conservation in crop). 

When designing gardens, ponds, or access ways, try 
to minimise waste space by using spiral, keyhole, and 
least-path systems, clumped plantings, and 
sophisticated interplants. 

Study and use edge effects, especially in relation to 
intercrop and in the construction of plant guilds, pond 
production, and fail-safe species richness in variable 
climatic regimes. 

Use appropriate patterns to direct energies on site, 
and to lay out the whole site for zone, sector, slope, and 
orientation benefits. This approach alone creates the 
most energy savings. 


Chapter 5 


If I go out shopping, a glance is sufficient to 
predict if I am likely to need an umbrella. 
However, long-term prediction of the weather, over 
a scale of more than about 10 days is a thankless 
task. This is because the dynamics of the 
atmosphere form a system whose behaviour is 
usually chaotic. The surface of the earth absorbs 
heat, and so heats the atmosphere from below, 
and this warm air rises. Heat is lost from the 
upper atmosphere, and this cooled air falls. A 
roughly hexagonal cellular array of vortices forms, 
with the ascending warm air feeding the 
descending cool air. 

(Arun Holden, New Scientist, 25 Apr ’85.) 

The glass is falling hour by hour 
The glass will fall forever 
But if you break the bloody glass 
You won't hold up the weather. 
(Louis McNeice.) 



Climatic factors have their most profound effect on the 
selection of species and technology for site, and are thus 
the main determinant of the plant, animal, and 
structural assemblies we can use. There is an intimate 
interaction between site and local climatic factors, in 
that slope, valley configuration, proximity to coasts, 
and altitude all affect the operation of the weather. Such 
factors as fire and wind effects are site and weather 
related. It is the local climate that inevitably decides our 
sector strategies. 

Although we will be discussing the individual 
weather factors that define climate, all these factors 

interact in a complex and continuously variable 
fashion. Interactions are made even more unpre¬ 
dictable by: 

• longer-term trends triggered by the relative 
interaction of the orbits of earth, sun, and moon; 

• changes included in the gaseous composition of 
the earth s atmosphere due to vulcanism, industrial 
pollution, and the activities of agriculture and forestry; 

• extra-terrestrial factors such as meteors, the 
perturbations in high-level atmospheric jet streams, the 
oceanic circulation, by fluctuations in the earth s 
magnetic field, and by solar flares. 

There is a general consensus that world climatic 
variation (the occurrence of extremes) is increasing, so 
that we can expect to experience successively more 
floods, droughts, periods of temperature extremes, and 
longer or very intense periods of wind. 

We have separated climatic studies from that of earth 
surface conditions, and there are climatologists who 
know little of the effects of forests, industrial pollutants, 
agriculture, and albedo (albedo is the ratio of light 
reflected to that received) on the global climate. There is 
no longer any doubt that our own actions locally 
greatly affect global and local climate, and that we may 
be taking unwarranted and lethal risks in further 
polluting the atmosphere. 

Because climatic prediction may forever remain an 
inexact science, we should always allow for wriability 
when designing a site. A basic strategy is to spread the 
risk of crop failure by a mixture of crop species, 
varieties, and strategies. This fail-safe system of mixed 
cropping is basic to regional self-reliance, and 
departure from such buffering diversity brings the 
feast-or-famine regime that currently affects world 

In house design, the interactions of thermal mass 
(heat storage) and insulation (buffering for temperature 
extremes) plus sensible siting permit us to design 


efficient and safe housing over broad climatic ranges. 
Strategies such as water storage and windbreak modify 
extreme effects. Many plant and animal species show 
very wide climatic tolerances, and local cultivars are 
developed for almost all important food plants. The 
variety of food grown in home gardens varies only 
slightly over a great many situations. 

As designers, we are as interested in extremes as in 
means (averages). Such measures as "average rainfall" 
have very little relevance to specific sites. Of more 
value are data on seasonal fluctuation, dependability, 
intensity, and the limits of recorded ranges of any one 
factor. This will decide the practical limits that need to 
be included in a design. 

People who are called on to design or instruct over 
wide climatic ranges would do well to read in more 
general treatments such as Eyre (1971) and James 
(1941), or in modern biogeographical texts. These 
treatments deal with world vegetation patterns and 
climatic factors. 

Total site factors related to land configuration will 
impose specific limits to any design; soil data will also 
be specific to site. There is, therefore, no substitute in 
any one design for local observation, anecdotes, 
detailed maps of local factors, lists of locally successful 
plant and animal species, and analysis of local soils. 

It is obligatory for any designer to study the regional 
long-term human and agricultural adaptations to 
climate. Above all, we should avoid introducing 
temperate (European) techniques and species to 
tropical and arid lands on any large scale. Aboriginal 
peoples were never so "simple and primitive" as we 
have been led to believe by the literature of their 
invaders. Native agricultural and pastoral management 
practices are often finely tuned to survival, are 
sometimes very productive, and above all are 
independent of outside aid. 

_5 1 2_ 


Most global climatic classifications are based on 
precipitation-radiation interactions as formulated by 
Vladimir Koppen (1918), and subsequently modified 
and updated by authors such as Trewartha (1954). 
Figure 5.1 is from the latter reference. More 
closely-defined plant lists can be given by reference to 
the "Life Zone" matrix developed by Holdridge (Figure 
5.2), which has enabled James Duke and others to 
annotate plant lists with concise climatic keys. Many 
plant compendia attach "zones of hardiness" to plant 
listings, commonly used in the USA. As given in 
Hortus Third, the zones are in Table 5.1. 

Measures or cut-off points are usually chosen that 
approximate the limiting boundaries for life forms, and 
are mainly good approximations of lethal or optimum 
ranges. The main qualifying factors on the broad 

classification of climatic factors an>: 

• special mountain conditions; 

• the modifying effects of coasts (and the extremes of 
continental interiors); 

• local energy transfer by winds and oceanic 
currents; and 

• long-term cyclic factors. 

Some problems in this area are: 

1. Instruments for accurate measurement are 
expensive, and often specific to a narrow range of the 
total spectrum of effects. 

2. Averages in such areas as precipitation and 
radiation often refer only to one part of the total 
spectrum. We have few long-term records of fog 
precipitation, dew, long-wave radiation, ultraviolet 
incidence, or gaseous atmospheric composition. 

3. We are aware that rain, sun, and wind interact in a 
dynamic and continuous fashion, so that averages 
mean little to a plant or animal subject to the normally 
changeable effects that may cover wide ranges of 
interactive measures. 

In this chapter, we are concerned only with the very 
broad climatic zones (design specifics for each climatic 
zone are given in later chapters). These have been 
grouped as follows: 

• TROPICAL: no month under 18°C (64°F) mean 
temperature, and SUBTROPICAL: coolest months 
above 0°C (32°F) but below 18°C (64°F) mean. In effect, 
frost-free areas. 

• TEMPERATE: coldest months below 0°C (32°F), 
warmest above 10°C (50°F) mean temperature, to 
POLAR: warmest month below 10°C (50°F) or in 
perpetual frost (8°C or less) mean. 

• ARID: mean rainfall 50 cm (19.5 inches) or less to 
DESERT: mean rainfall 25 cm (10 inches) or less. 
Includes sub-humid, or any area where evaporation 
exceeds precipitation. 

_ 53 _ 



Dense cold air flows continually off the polar ice caps. 
This high-pressure or down-draught air spirals out of 
the polar regions as persistent easterlies which affect 
high latitudes (60-80°) near the ice-cap themselves. 
Long spokes of this air curve outward to Latitude 30°. 

As the spiral itself is caught up in (and generated by) 
earth spin, these cold cells of air drive a series of 
contra-rotating low-pressure cells (turning clockwise in 
the southern hemisphere and anti-clockwise in the 
northern). These in turn mesh with rotating spirals of 
high-pressure air which have risen at the equator, and 
are falling at Latitudes 15-40°. 

The high-pressure mid-latitude cells turn anti¬ 
clockwise in the southern hemisphere and clockwise in 




A basic world classification; mionor subdivisions are specified in 
detailed maps or basic references. 

M*AA‘- Jjirwww cs*rt6K**e.n 

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Boreal forest 


Temperate grassland 9.5 2 

Temeprate forest 


Tropical shrub and 
Tropical savannah 
and grassland 
Tropical deciduous 

Tropical evergreen 


TABLE 5.1 -— 



Av. Annual Min. Temp. 

Av. Annual Min. Temp. 





Below -50 

Below -45 

Arctic tundra 


-50 to -40 

-45 to -40 

Cold prairie and conifers 


-40 to -30 

-40 to -34 

Conifers and mixed forests 


-30 to -20 

-34 to -29 

Cold interiors of continents 


-20 to-10 

-29 to -23 

Mixed forests, cool prairies 


-10 toO 

-23 to -18 

Broadleaf and deciduous 




-18 to-12 

Broadleaf forests 


10 to 20 

-12 to -7 

Arid grasslands, savannah 


20 to 30 

-7 to -1 

Semi-arid coasts and basins 


30 to 40 

-1 to 4 

Sub-tropical, palms, coasts 


40 to 50 

4 to 10 

Tropical forests, deserts 


over 50 

over 10 

Equatorial rainforests, monsoon 

the northern. Thus from Latitude 50-20°, and in the 
"roaring forties ', about 15-18 alternating high-low 
pairs of great cells circulate the earth, all of them as 
smaller spiral systems around the great polar spiral 
itself (Figure 53). On westerly coasts, the alternation of 
cold polar and warm high pressure air arrives at about 
10 -day intervals, although some great high-pressure 
cells persist in place, thus blocking westward 
movement of winds and creating static oceanic 
conditions that can affect oceanic over-turn, and thus 
fisheries (e. g. the el NiHo effect). 

These great processions are disturbed and deflected 
by continents, stubborn high-pressure cells over cool 
land masses, and the relative intensity of the air cells, so 
that irregular cold-warm fronts arrive at any one site. 
Just as polar air is sometimes drawn strongly towards 
the equator in the lows, so warm tropical air masses are 
entrained in the outer circulation of the highs and bring 
heavy warm rains towards the poles. High level 
jetstreams may speed up or block this procession and 
the jetstream itself may also break up under stresses 
caused by shear. 

The disturbances and impedences in the system cause 
cold fronts to pile up against each other and deflect 
polewards at high-pressure cells, and a sequence of 
warm- and cold-front rains (the cyclonic or spiral 
rains) of earth results. 

All these wind belts shift north or south with the sun 
annually, and to some slower extent as a result of the 
18 . 6 -year moon cycle, so that periods of drought and 
excessive rain can result. The system appears chaotic, 
and subject only to short-term prediction, but of late we 
are learning to assess some of the effects of the 
long-term cycles. 

The great spiral circulation of the south polar regions 
is shown in Figure 5.3. About 12-18 cold fronts (cloud 
bands) circle from west to east around the poles. 

arriving as "cyclonic fronts" every 10 or so days on 
coasts in that region. They affect areas up to 30° south, 
with four or so large fronts continuous with (and 
probably driving) cloud up to 10 ° south or north 
latitude, mostly along the western margins of South 
America, Africa, and the south Atlantic. It is now clear 
that it is the oceanic circulation that drives the air 
masses, rather than the opposite. 

The fronts are dragged in a curve to the west as the 
earth spins to the east. Each cloud front is a result of the 
meeting of cold polar and warm sub-polar air masses 
or high-pressure cells. The low-pressure areas rotate 
clockwise, the highs anti-clockwise in a series of 
cog-like spirals or tori that travel every 3-4 months 
around the poles. Rotation is in the opposite sense in 
the northern hemisphere. It is the cold, dense, dry polar 
air sweeping off the ice-caps, and the hot rising air of 
the equatorial calms which drives these great wheels; 
clear-air (descending) intrusions are of hot-dry and 
cold-dry continental air (Australia, Africa) or air 
descending from the equatorial (rising) congruence 
(Figure 5.4). 

in the next sections of this chapter, I will be 
discussing CLIMATIC FACTORS under parts, as below: 

• Precipitation (rain, fog. dew, evaporation-5.4); 

• Radiation (light, heat, frost, solar input-5.5); 

• Winds (normal winds, hurricanes and tornadoes - 


• Landscape effects (altitude, valleys, slopes-5.7); and 

• Latitude-altitude factors (5.8). 

_ 5 A _ 


There are two basic inputs to precipitation: that of 
rainfall, snow, and hail (WATER FALLING from the 


clouds), and that of CONDENSATION (water 
condensed or trapped from sometimes clear air or fogs 
by cool surfaces). Although the latter may be of critical 
importance on seaward slopes and at higher altitudes 
'Cloud forests), the only reliable and widespread 
measures we possess are of "rainfall". World rainfall 
averages about 86 cm (34 inches). While we may take 50 
cm (20 inches) of rainfall or less as semi-arid, and 25 cm 
• 10 inches) or less as arid and desert, we can locally 
experience seasonal or relative aridity due to long-term 
cycles and weather effects caused by periodic 
fluctuations in jetstreams or oceanic currents in any 
climate. Longer periods of increased aridity can also be 
caused by deforestation on a broad or local scale. 

It is because of the potential for changes in 
precipitation that we give so much space in later 
chapters to water storage strategies and the 
conservation of water. Water promises to be the main 
limiting factor for survival and growth, and the major 
future expense of food gardens and agriculture. Thus, 
any strategy we can adopt to generate, conserve, or 
store water is critical to our design approach. Any 
gardener knows that climatic averages are at best a very 
general guide to precipitation effects in the garden or 
orchard. It is a much safer strategy to see to it that both 
the species chosen and water strategies developed 
ensure some yield in "drier than usual" conditions. 
After all, a fish population out of water for an hour is as 
dead as if a year-long drought were in effect. 

Our annual gardens and crops are also susceptible to 

short-term changes in available water. People live, and 
garden, in average annual rainfalls of 10 cm (4 inches) 
or less, and they manage to both exist and produce 
crops. Exotic (non-local) water enters dry regions as 
rivers and underground aquifers, and this enables us to 
make judicious use of that water and to implement a 
great variety of local strategies to cope with the lack of 
actual rainfall. 

Rainfall averages are best used as broad indicators 
rather than as definable limiting factors. Of far more 
use to us is the expected DISTRIBUTION of rainfall 
(including extremes such as 100 -year flood records) 
and data on the INTENSITY of rains, as these factors 
are a limiting influence on the size of road culverts, 
dam spillways, and the storage capacity needed to see 
us over dry periods. Flooding histories of sites and 
districts often indicate the real limits to the placement 
of plant systems, fences, and buildings, so that attention 
to flood records avoids future costs and disappointment 
If flood data is omitted, life itself can be at risk in 
intense periods of rain. 

As precipitation rises, available light decreases. Thus, 
in extremely cloudy industrial or fog-bound humid 
climates, light becomes the limiting factor for some 
plants to ripen or even flower. At the dry end of the 
rainfall spectrum (as we reach 50 cm or 20 inches mean 
rainfall) sun is plentiful and evaporation in excess of 
precipitation becomes the limiting factor. That factor 
determines our arid-land storage strategies, just as the 
depth of seasonally frozen soils and ice cover 
determines water reticulation strategies in cold 

Rainfall is conveniently distinguished by the 
processes causing rain as: 

• OROGRAPHIC: the cooling of air as it rises over 
mountains or hills. 

• CYCLONIC or FRONTAL: the over-riding of cool 
and warm air masses of the polar circulation. 

• CONVECTIONAL: columns of hot air rising from 
deserts or oceans into cooler air. 

Apart from rain, we have dew and fog. DEW is a 
common result of clear nights, rapid radiation loss, and 
a moist air mass over coasts and hills. It occurs more 
frequently in clear-sky deserts than in cloudy areas, 
and a slight wind speed (1-5 km/h) assists the quantity 
deposited. Both still air and strong winds reduce 
dewfall. Intensity of deposition is greatest 3-100 cm 
above ground level; the highest deposition due to areas 
of dry ground, the lower due to wet earth, which chills 
less quickly. 

Not to be confused with dew (a radiation heat loss 
effect from earth with clear night skies) is the moisture 
found on leaves above warm damp ground on cloudy 
nights. This is either GUTTATION (water exuded from 
the leaves) or DISTILLATION from rising ground 
vapour; it represents no net gain to total precipitation. 
The waters of guttation cling to the tips of leaves, dew 
to the whole leaf area. 

Only in deserts is the 4-5 cm (1-2 inches) of dew per 
year of any significance in precipitation. Dew in deserts 


can be regarded as an accessory to, rather than a 
replacement for, trickle irrigation. Dew may be 
captured by building piles of loosely-stacked stones, 
where low night winds cool rock surfaces and dew can 
accumulate to dampen the ground below. In the Negev 
desert and other dry areas, some plants are associated 
only with these dew condensers. Each mound of stones 
may suffice to water one tree (Figure 5.5). Very large 
radiation traps, such as those on Lanzarote in the 
Canary Islands (Figure 5.6) may grow one grape vine in 
each hole. 

The most efficient dew-collectors are free-standing 
shrubs of about 1-2 m (5-6 feet) in height. Groups or 
solid stands of plants and grasses do less well in 
trapping dew, and this may help to explain the discrete 
spacing of desert plants, where perhaps 40% more dew 
is trapped on scattered shrubs than would be caught in 
still air, or on closed vegetation canopies. 

It is possible to erect metallic mesh fences 1 m (3 feet) 
or so high, and to use these as initial condensers in 
deserts, growing shrubs along the fence drip-line, and 

moving the fence on after these plants are established. 
In Morocco such fences are proposed for deforested 
coastal areas. 

FOG forms where warm water or the vapour of 
warm rain evaporates into cool air, or where cold 
ground chills an airstream and condenses the moisture. 
Chang (1968) concisely differentiates between: 

1. RADIATION GROUND FOG: where, on clear 
nights, hollows and plateaus cool rapidly and fog 
forms, often in much the same pattern as the frosts of 

2. ADVECTION FOG: where cold offshore currents 
condense the moisture in warm sea airstreams. These 
are the coastal and offshore fogs that plague many 
coasts such as that of Newfoundland and parts of 
northwest Europe. 

humid airstreams are carried up hill slopes, and 
condense as the air cools. 

Unlike dew, fogs can provide a great quantity of 
moisture. Chang gives figures of 329 cm (128 inches) for 



Polar ice cap high pressure 
Polar easterlies 

60°N Interpolar calms 

3o*n-— 30* N Horse latitudes 

NE Trades 
Summer monsoon 
• 0* Equatorial calms (Doldrums) 
Summer Monsoon 

SE Trades 

30° S Horse latitudes high pressure calms 

Roaring Forties (Westerlies) 

" 60° S Sub polar low pressure calms 

Polar easterlies A.A' Primary cold air cells driven by ice 
Polar ice cap high pressure chilling at the poles. 

B. B' Secondary cells driven by A and C cells. 

C. C' Primary hot air cells driven by equatorial 




Loose piles ol stone of less than 1 m high condense moisture from 
night air movement. Free air flow is permitted between stone piles. 

Table Mountain, South Africa, and 127 cm (50 inches) 
for Lanai (Hawaii) from fog drip alone. In such areas, 
even field crops may thrive without irrigation. 
Typically, bare rock and new soil surfaces are colonised 
with lichens and mosses on sea-facing slopes, while 
rainforest develops on richer soils. Much of New 
Zealand experiences upslope fog precipitation, and 
unless burnt or cleared to tussock grasslands, dense 
forests will develop; the irregular canopy of such forests 
are excellent fog condensers. Even with no visible fog, 
trees will condense considerable moisture on sea-facing 
slopes with night winds moving in off warm seas over 
the land, and encountering the cool leaf laminae of 

In the very humid air of fog forests, giant trees may 
accommodate so much moisture, and evapotran- 
spiration is so ineffective if fogs and still air persist, that 
more large limbs fall in still air than in conditions of 
high winds (which tend to snap dry branches rather 
than living limbs). It is an eerie experience, after a few 
days of quiet fogs, to hear a sudden "thump!" of trees in 
the quiet forests. Almost permanent condensation fogs 
clothe the tops of high oceanic islands, and hanging 
mosses and epiphytes rapidly develop there, as they do 
at the base of waterfalls, for the same reasons (free 



Cold air sinks in these cinder-covered pits, condenses on cinder. 

moisture particles in the air). 

5.5 _ 



Incoming global radiation has two components: 
DIRECT SOLAR RADIATION penetrating the atmo¬ 
sphere from the sun, and DIFFUSE SKY RADIATION. 
The latter is a significant component at high latitudes 
(38° or more) where it may be up to 30% of the total 
incoming energy. Near the poles, such diffuse radiation 
approaches 100% of energy. We have reliable measures 
only of direct solar radiation, as few stations measure 
the diffuse radiation which occurs whenever we have 
cloud, fog, or overcast skies. 

Light and heat are measured in WAVELENGTHS, 
each set of which have specific properties. We need to 
understand the basics of such radiation to design 
homes, space heaters, and plant systems; to choose sites 
for settlement; and to select plant species for sites. 
Table 5.2 helps to explain the effects of differing 

A minor component of terrestrial radiation at the 
earth's surface is emitted as heat from the cooling of the 
earth itself. The greater part of the energy that affects us 
in everyday life is that of radiation incoming from the 

Of the incoming or short-wave radiation (taken to be 
100 % at the outer boundary of the atmosphere): 

• 50% never reaches the earth directly, but is scattered 
in the gases, dust, and clouds of the atmosphere itself. 


TABLE 5.2 "- 







Actinic or Ultra Violet: only 1.5-2% reaches 
the Earth, most being absorbed by the 
ozone layer. 

Causes sunburn, skin cancers. 

May be increasing due to ozone 
layer destruction. 







Visible light (white light) composed of: 






The rainbow colours visible as 
differentiaited by water vapour or a 
prism. About 41% of radiation 
reaching Earth. 




3,001 + 

Heat (long wave radiation) and radio waves 

Far red 

Infra red 

Emitted by bodies heated by 
combustion, or those which have 
absorbed short wavelengths. 

About 50% of radiation reaching 

Of this 50%: 

— half is reflected back into space from the upper 
layers of cloud and dust. 

— half converts (by absorption) into long-wave or 
heat wavelengths, within the dust and clouds that act 
as a sort of insulation blanket for earth. 

• 50% reaches the earth as direct radiation, mostly 
falling on the oceans. Of this 50%: 

— 6%, a minor amount, is again lost as reflection 
to space. 

— 94% is absorbed by the sea, earth, and lower 
atmosphere and re-emitted as heat or converted to 

Of the outgoing, or terrestrial, radiation (absorbed 
solar radiation and earth heat, including the added heat 
released by biological and industrial processes and 
condensation), the heat that drives atmospheric 

67% is re-radiated to space, and lost as heat. In the 
atmosphere, therefore, most heat is from this re¬ 
radiated heat derived from the surface of the earth. 

• 29% is released from condensing water as sensible 

Ozone in the upper atmosphere absorbs much of the 
ultraviolet light, which is damaging to life forms. 
Carbon dioxide, now 3-4% of the atmosphere, is 
expected to rise to 6%, and cause a 3°C (5.5°F) heating 
of the earth by the year 2060. This process appears to be 
already taking effect on world climate as a warming 
trend, and will cause sea level changes. 

The effect of radiation on plants is different for 
various wavelengths, as in Table 5.3. 

Other sources of light for the earth are the moon (by 
reflection of sunlight) and star light. Although weak, 
these sources do affect plant growth, and even fairly 
low levels of artificial light affects animal and plant 
breeding. The major effects of radiation overall are: 

• PHOTOSYNTHESIS in plants, the basis of all life 
on earth. 

• TEMPERATURE effects on living and inorganic 
substances, much used in house design. 

• FLOWERING or GERMINATION effects in plants, 
of basic importance to the spread of specific plant 
groups; this includes the day-length effect. 

Plants actively adjust to light levels by a variety of 
strategies to achieve some moderate photosynthetic 
efficiency. They may keep the balance between heat and 
light energies by adopting solar ranges to suit the 
specific environment (silvery or shiny leaves where 
heat radiation is high; red leaves where more of the 
green spectrum is absorbed and less heat needed). 
Leaves may turn edge-on when light and heat levels 
get too high, or greatly enlarge their surface area under 
a shady canopy. Trees have larger leaves at the lower 


When we look at any object, we see it by receiving the 
wavelengths of the light it REFLECTS or screens out. 
Thus, many plants reflect green/blue wavelengths, 
while flowers reflect a wider spectrum of light, 
becoming conspicuous in the landscape. About 10% of 
light penetrates or is transmitted by foliage, although 


he canopy of rainforests in very humid areas (tropical 
r temperate) may permit only 0.01% of light to pass 
hrough to the forest floor. Absorbed light, as heat, is 
e-radiated or used in growth. 

In addition to leaf colour, plants have bark surfaces 
anging from almost white to almost black, the latter 
;ood absorbers and heat radiators, the former good 
eflectors. Leaf surfaces may vary from hard and shiny 
o soft, rough, and hairy. Typically, waxy leaf surfaces 
re found in coastal or cold areas, and in some 
inderstory plants, while woolly leaf surfaces are found 
n deserts and at high altitudes. The waxiness often 
jives a greater reflection of light regardless of colour, 
vhile dark or rough surfaces absorb light, so that dark 
vergreen trees become good radiators of heat. 

All of these factors (colour, reflection, heat radiation) 
are of as much use in conscious design as they are in 
nature, and can be built in to gardens or fields as aids to 
microclimatic enhancement. 


The albedo (the reflected light value) of plants and 
natural surfaces determines how they behave with 
respect to incoming radiation. The light reflected goes 
back into the atmosphere, or is absorbed by nearby 
surfaces and by structures such as greenhouses. The 
light absorbed is converted into long-wave radiation, 
and is re-emitted as heat (Figure 5.10). Soils and 
similar dense materials normally absorb heat from 







-280 (UV) 

UV or actinic 

Kills plants and animals. Germicidal. 

31-315 (UV) 

UV or actinic 



Lkl i \ i m 11 ■"! ' r \t T11 1 iii M - H 



Strong absorption and growth in plants. 
Effective photosynthesis. Transmitted by 
fibreglass, several plastics. 


II lill 



Strong absorption and photosynthesis, 
photoperiodic behaviour=day length effect. 


Red-Far Red 

Plants elongate, important for seed germina¬ 
tion, flowering, photoperiodism. fruit 


Infra Red 

Absorbed and transpired into heat by plants; 
no strong growth effects. 


daytime radiation to a depth of 51 cm (20 inches) or so. 
As this takes time, the build-up of soil heat lags a few 
hours behind the hourly temperatures. Re-radiation 
also takes time, so that such absorbing surfaces lose 
heat slowly, lagging behind air temperatures. Thus we 
have our lowest soil temperatures just after dawn. The 
radiation loss at night produces frost in conditions of 
still air lin hollows, on flats, and in large clearings of 
9-30 m (30-100 feet) across or more in forests|. Some 
frost (ADVECTION frost) flows as cold air down hill 
slopes and valleys to pool in flat areas. Frost forms 
rapidly on high plateaus. Dense autumn fogs often 
indicate the extent of winter frosts, and are clearly seen 
from high vantage points. 

As designers, we use water surfaces, reflectors, and 
specific vegetational assemblies for forest edges. Table 
5.4 gives an indication of the value of diffuse reflectors, 
as albedo. A perfect reflector refuses 100% of light 
(mirrors); a perfect absorber is a BLACK BODY that 
absorbs all light and converts it to heat. 

The fate of incoming waves encountering an object or 
substance is either: 

• REFLECTED: turned away almost unchanged, as 
light off a flat mirror or off a white wall. 

• REFRACTED: sharply bent or curved, as is light in 
water, images in curved glass, or sea waves around a 

• ABSORBED: soaked in, as when a black object 
soaks up light. This changes the wavelength (light to 
heal or short to long wavelength). All absorbed light is 
emitted as heat. 

• TRANSMITTED: passed through the object. 









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Plant growth (photosynthesis) relies on two narrow bands ot light, is 
damaged by extreme ultraviolet or heat wavelengths. 

Different substances pass on, or are ’’transparent" to, 
different wavelengths due to their molecular structure. 

Thus it is by our choice of the materials, colours, or 
shapes of fabricated or natural components that we 
manipulate the energy on a site. We can redirect, 
convert, or pass on incoming energy. The subject of 
radiation ties in with areas of technology as much as 
with natural systems, and this section will therefore 
serve for both areas of effect. 

The earth itself acts like a "black body ”, accepting the 
short wavelengths from the sun, and emitting after 
absorption the long wavelengths from the surface and 
atmosphere. Table 5.2 deals mainly with the short 
wavelengths, as they are those coming in as light and 
heat from the sun. The long wavelengths we experience 
are those re-radiated to earth from the atmosphere, or 
emitted by the hot core of earth. Curiously, snow is also 
a black body in terms of heat radiation. Black objects 
such as crows or charcoal can become effective 
reflectors if their shiny surfaces are adjusted to reflect 
radiation (a crow is black only at certain angles to 
incoming light). 

HEAT (Longwave radiation) 

It is difficult to store heat for long periods in field 
conditions, although it can be done in insulated water 
masses or solids such as stone and earth. There is some 
heat input every day that the sun shines or diffuse sky 
light reaches the earth. The mean temperature of the 
earth is 5°C (41 °F), of the air at or near ground level 
14°C (57°F), and of the outer layers of the atmosphere 
-50° to -80°C (-90° to -144°F). Normally, we lose about 
1°C for every 100 m increase in altitude (3°F per 1000 

m tKi -renp i7is-K ' 


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Most heat is trapped by moisture, dust, or gases in the atmosphere; a 
little is emitted by the Earth itself 


TABLE 5.4 





The perfect reflector" 



White, smooth paint 



Clean fresh snow 



White gravel 



Dense white clouds 



Calm water 
(Sun 15° elevation) 



Adapted desert shrubs 



Sand dunes 



Sandy soils 



Dry hay 



Wood edges 



High sun. rough water 



Young oaks 



Young pines 



Dark soils 



Fir forest 



"The perfect black 



feet). In most conditions we experience a reduction in 
temperature with increasing altitude, but in many 
valleys, or on plains surrounded by mountains, cool air 
from the hills or cold air generated by rapid radiation 
loss from soils creates a condition where layers of dense 
cooler air are trapped below warmer air, and we have a 
TEMPERATURE INVERSION. It is in such conditions 
that fog, smog, and pollution can build up over cities 
lying in valleys or plains, where wind effect is slight. 
Such sites must be carefully analysed for potential 

designers as much as flood periodicity. Livelihoods 
should not depend on broadscale plantings of frost- 
susceptible crops in these situations. 

For building and garden designs, we should be aware 
of just how heat is stored and transmitted. First, we 
need to distinguish between lowgrade heat transmitted 
by CONVECTION, or the passage of air and water over 
slightly heated surfaces. It is this effect which operates 
in valley climates, and which creates valley winds. Cool 
air is heavier (more dense) than heated air; the same 
factor holds true for water or liquids, and other gases 
(and fluid flow generally). 

Thus, providing heated air or water is contained in 
pipes or ducts, a closed loop circulation can be set up 
by applying heat to the lower part of that loop, 
providing that a least rise or height difference of 40 cm 
(about 18 inches) is built in to the loop; any greater 
height is of course also effective in producing a 
thermosiphon effect (Figure 5.11). This is the effect 
used in refrigerators driven by flames or heat sources. 

In the atmosphere, columns of heated air over land 
ascend as an "Overbeck jet" (Figure 4.13), and at the top 
of this column, condensation and rain may occur as the 
air is cooled in the upper atmosphere. Such 
convectional rains are responsible for the mosaic of 
rainfall that patterns the deserts. 

Convection loops will not occur in closed rooms, 
where hot air (at 8-10 e C (1518°F) higher temperturel 
sits in a quiet or stratified layer below ceilings. As air is 
difficult to heat, and stores little heat, air convection is 
not an efficient way to heat building interiors, although 
it is the main "engine" of atmospheric circulation in the 
global sense. 

Thermpsiphons are useful in transferring heat from 
solar ponds or flat plate collectors to home radiators or 
hot water tanks; we should, wherever possible, site 
these heat collectors 0.5 m (1.6 feet) below the storage 
or use points so that they are self-regulated thermo¬ 


As in the case of precipitation, it is advisable to 
research temperature extremes for site. Poultry (and 
many wild birds) do not survive temperatures greatly 
in excess of 43°C (109°F), nor do plants survive 
transplant shock from nursery stock when soil 
temperatures exceed 36°C (97°F), whether in deserts or 
in compost piles. Many plants are frost-affected at or 
below 0°C (32°F), and below this, sustained periods of 
lower temperatures will eliminate hardier plant species 
(even if well-established). Thus, the very widespread 
and sometimes economically disastrous black frosts 
that affect whole regions should be noted by site 

FIGURE 5.10 


Glass is less permeable to long (heat) radiation, thus it ‘traps' radiated 
heat but transmits short-wave light 





a**<r*s.p Anp 




Heat flows from warmer to colder bodies, and just as 
warm air transfers heat to cool solid bodies by day, so 
warm bodies can heat large volumes of air at night. 
Bodies that are heated expand, decrease in density, and 
(where there is freedom to move) heated air or water 

The common heat unit is that needed to raise one 
gram of water from 14.5°C to 15°C. In terms of 
incoming radiation, gram calories per square centimetre 
(g/cal/m ? ) are termed LANGLEYS; the sun provides 
about 2 Langleys/minute to the outer atmosphere. 

The quantity of heat received on earth is greatly 
affected by: 

• latitude and season (the depth of atmosphere); 

• the angle of slopes (which in turn affects reflection 
and absorption); and 

• the amount of ice, water vapour, dust, or cloud in 
the air above. 

This means that the Langleys received at ground level 
vary widely due to combinations of these factors. 
Nevertheless, most homes receive enough sunlight on 
their sun-facing areas to heat the water and space of the 
house, if we arrange to capture this heat and store it. 

However, even when the sun is directly overhead on 
a clear day, only 22% of the radiant energy penetrates 
the atmosphere (1 atmosphere depth). In polar areas, 
where the slanting sun at 5° elevation passes obliquely 
through at a distance of 11 atmospheres, as little as 1 % 
of the incoming energy is received! Slope has similar 
profound effects, so that slopes facing towards the poles 
receive even less energy from radiation. 

It follows that siting houses on sun-facing slopes in 
the THERMAL BELT is a critical energy-conservation 
strategy in all but tropical climates, when siting in 
shade or in cooling coastal windstreams is preferred. 
Sun-facing slopes not only absorb more heat, but drain 
off cold air at night; they lie below the chilly hilltops, 
and above the cold night air of valleys and plains 
(Figure 5.12). 

In hill country and mountains, these thermal belts 
may lie at 1000-5000 m. (3,280-16,400 feet), and on 
lower hill slopes at 100-200 m. (330-650 feet), whereas 
in hot deserts the frost levels may only reach to 10-15 
m. (33-49 feet) up the slopes of mesas. Each situation 
needs specific information, which we can gain from 
local anecdotes, the observation of existing plants, or 
trial plantings of frost-susceptible species. 

Winds travelling from warmer to cooler regions, or 
the opposite, bring ADVECTED (exotic, or out of area) 
warmth and cold to local regions. Thus we speak of 
advection fogs where these come inshore from coasts, 
and advection frosts when cold air flows down 
mountain slopes to pool in hollows. 

The invasion of cool areas by warm advected air 
causes moisture condensation, which is critical to 
precipitation in forests, but a nuisance in enclosed 

buildings. Thus, we should attempt to bring only dry 
warm air into wooden houses, or provide ways to 
direct condensation moisture to the house exterior. 

Intermediate grades of heat can be transmitted by 
CONDUCTION, as when solids are in contact. It is in 
this way that we heat an entire floor or wall by heating 
it in one place, and this is the basis of the efficiency of 
the slab-floored house, where the floor is previously 
insulated from surrounding earth. In open 
(uninsulated) systems, conduction effects are local, as 


A "Low grade' heat is conducted from solid to solid or fluid to fluid by 
contact Insulation is effective in trapping such heat 
B 'Medium grade heat' rs convected ' by the movements of fluids or 
gases, as in air. wind, or water. Draught-proofing conserves this heat 
Heated fluids rise. 

C “High grade heat* travels by straight-line radiation in all directions 
and can only be conserved by reflective (dust-free) surfaces or 
mirrors.This is how the sun heats the Earth 


heat is fairly rapidly radiated from solids or soil 
surfaces. Pipes buried in hot solid masses have heat 
conducted to their contents, or hot water pipes conduct 
heat to slab floors in which they are buried; such 
heating is most efficient in homes. 

Intense heat trapped in solids and liquids is 
RADIATED, which is the effect transmitted across space 
by the sun. Radiant heaters affect air temperature very 
little, but radiation heats other solids and liquids (like 
our bodies) or dust in the air. Thus, we can keep very 
warm even in a draughty or cool room by the use of 
radiant electric, gas-fire, or wood-heated massive 
stoves; these are very efficient space heaters. As 
radiation crosses space, and is nondirectional, focused 
radiation can produce very intense heat locally. 


Most or all Arum lilies, and species such as Philo¬ 
dendron selluum store fats which are "burnt" to create 
heat, so that the flowers heat up. Philodendrons may 
register 46°C (115°F) when the air is 4°C (39°F). and 
crocuses heat up to 15°C (27°F) above the ambient air 
temperature. The warmth generated is probably used to 
attract flies and heat-seeking insects to the pollen. 
Some plants (skunk cabbage, Symplocarpus foetidus). 
however, may use their heat to melt a hole in the 
spring snow, and so protect the blooms from cold |at 
20-25°C (36-45°F) extra heatl as well as to provide a 
cosy incubator for the rest of the plant's growth" {New 
Scientist, 9 May 85) and to scatter odorous scents that 
attract pollinating flies. More amazingly, the shape of 
the first leaf of this species creates a vortex (from wind) 
that is contained within the hot leaf and carries pollen 
down to the unpollinated lower flowers, thus achieving 
fertilisation, in cold winds, without the presence of 

As all these "heaters" may have unpleasant smells, we 
should use them with caution. Understorey clumps of 
such species may assist frost-tender, fly-pollinated, or 
heat-starved plants, just as tall interplant systems may 
assist general heat requirements for some ground crops. 

The effect of soil temperatures alone on germination of 
a wide range of vegetable seeds can be profound. 
Between 0°-38°C (32°-100°F) the time to germinate (in 
days) can be reduced to one-tenth or one-fourth of that 
in cold soils by increasing soil temperatures. At the 
extremes of this temperature range, however, we find 
many plants have limiting factors which result in no 
germination. While almost all vegetable seed will 
germinate in soils at 15-20°C (59-68°F), such oddities as 
celery refuse to germinate above 24°C (74°F), and many 
cucurbits, beans, and subtropicals do not germinate 
below 10°C (50°F). Thus, we are really talking about 
waiting until 10°C is reached, or warming up the soil in 
greenhouses or with clear or black plastic mulch in the 
field before planting. Sometimes just the exposure of 
bare earth to the sun helps. A simple thermometer 
inserted 2.5 cm (1 inch) in the soil suffices to measure 
the soil temperature, or a special soil thermometer can 
be purchased. For specific crops, we can consult such 
tabulations as are found in Maynard and Lorenz 
(Knotts Handbook for Vegetable Growers. 1980, Wiley, N.Y.) 

A second effect on germination is light itself, e.g. 
carrots need a definite quantity of light, and are usually 
surface-planted to effect this. We can surface-scatter 
such seeds, or first soak them overnight and then subject 
them to a day under a low-wattage light bulb or in the 
open before planting and covering them lightly (they 
react to this light only if wetted first). Larger seeds 
usually accept burial and germination in the dark, 
while some weed seed and desert seed will germinate 
deep-buried. For a few weed species such as wild 
tobacco, a mere flash of light (as when we turn over a 
clod of soil) suffices to start germination. 

Next we come to cold , and we speak of the 
Cold-area seed, and specifically tree and berry seeds 
from boreal or cold areas, should spend the period from 
autumn to spring in a refrigerator when taken to 
warmer climates. Apple seeds stored in sand or 
chestnuts in peat sprout in this way, and can be potted 
out as they shoot. This in fact reproduces the exposure 
to cold (at about 0°-5°C (32°-40°F)l that they normally 
experience at the litter level in cold forests or marshes. 
Wild rice and other "soft" aquatic seeds are stored in 
open ponds, or under water in an ordinary refrigerator. 

Stratification can often be accomplished by keeping 
such seeds in sand or peat (or water for aquatics) in 
cold shaded valleys, or under open cool trellis in warm 
climates. They can be checked on late in winter and 
spring for signs of germination. The opposite of this is 
heat treatment, such as we can give to many tree 
legume seeds, by heating in an oven at 95°C (200°F) for 
a 10-20 minute period, or by pouring very hot 
(near-boiling) water over them, or by burning them in a 
light straw fire. 

Many older gardeners will also feed seeds to 
themseives (in sandwiches), or their animals (chicken or 
cattle), collect the manure, make a slurry of it, and sow 
such seeds as tomatoes, berries, and tree legumes. The 


voyage through the digestive system is a compounded 
process of acid/alkali, hot/cold, mechanical cracking in 
teeth or in bird crops, and packaging in manure to 
which a lot of seeds are adapted. 


Day length (in fact, night length, but we will take the 
day side) varies over latitudes, and flowering plants are 
adapted to bloom and set seed in response to specific 
day lengths and the change of seasons. While many 
plants are DAY NEUTRAL and will flower if other 
factors are satisfactory, some will not flower at all in 
shorter or longer day-lengths than those to which they 
are adapted. This can be put to use, as when we transfer 
a tropical (short-day) corn to a temperate (long-day) 
hot-summer climate, and get a good green-leaf crop as 
fodder, or take tobacco from temperate to cool areas 
and get leaf rather than seed production. The same goes 
for some decorative foliage plants. But this effect is in 
fact the reason for choosing varieties from local 
growers, or selecting for flowering in new introductions 
so that a local seed source is available for all those crops 
we want in seed. 

In New Guinea highlands (short days), cabbages 
from long-day climates may never flower, and some 
Brassicas reach 1-3 m in height, the leaves being 
plucked off at regular intervals for vegetable fodder, 
and the plant cut down only when too tall to reach! 

Latitudes have specific day lengths as follows: 

A 7*6 CieAfiJsJO fifjp nr should ft&>vce= FnoST 


FIGURE 5.13 


Frost loss IS less in small steep-walled clearings that are about halt 
the width of tree height 

• LOW LATITUDES (0-30°): Usually tropical 
climates, with colder mountain climates; equal or 
near equal days and nights. 

• MID LATITUDES (30-50°); Cool to temperate 
climates with boreal mountain regions; long summer 
days and short winter days. 

• HIGH LATITUDES (>50° ): Very long summer 
days, and probably good radiation from diffuse light all 
the growing season. No plants grow in winter. 


Frost is caused by radiation loss (rapid cooling) of the 
earth on clear nights, in still air. To reduce frost on any 
site (or in a small pit), it is necessary to have a 
steep-sided clearing or pit so that radiation is restricted 
to a small area of the sky. In such clearings, we have 
two effects: radiant heat from the vertical edges plus the 
obscuring of the horizon (hence less radiant heat loss at 
night). The proportion of heat loss on a cold night is 
proportional to the area of the night sky that is visible 
to the object losing heat. For example, a mouse in a 
cardboard tube in the ground loses very little heat, but 
a mouse on a mound on a flat sight is exposed to the 
whole sky and loses a great deal of heat. 

The second factor is that the pit or clearing should be 
small; large clearings will create or contain more frost. 
The rule is to make the clearing (or pit) about one-half 
as wide as high, and to keep the sides trimmed to 
vertical. In forests, such clearings should not exceed 30 m 
across (Figure 5.13). 

It is necessary, therefore, to try to build up a complete 
crown cover to prevent frost on a site, and this is best 
done in stages. For example, we could plant the whole 
area to frost-tolerant legume like silver wattle (Acacia 
deall'ata), then plant semi-hardy fruits in the shelter of 
these, eventually cutting back the Acacia as the 
frost-sensitive, protected trees gain height. It is 
obviously necessary to assist this process by supplying 
water to the selected trees, and this may also help 
ameliorate the frost effect on nights of high risk. 

The effect of trees on soil moisture and frost may be 
profound at edges and in small clearings, as the tree 
crowns obviously create their own water distribution 
on the ground. Crown drip can direct in excess of 100% 
of rain to a "gutter*' on the ground, and for some tree 
species with down-sweeping limbs and leaves, this is a 
profound effect. At the rain-shadow edges of forests, 
dry areas are to be expected What makes this effect 
more pronounced is that the ’wet" edges are more often 
than not also away from the sun (most rain comes from 
the polar side of sites). Figure 5.14. 

The sunny edges of the forests help protect seedlings 
from frost, and these and small clearings are used to 
rear small trees, or to plant them out in frosty areas. 

Some implications for designers are as follows: 

of severe direct or diffuse radiation, and especially 
where the atmosphere is thin (on mountains), where 
albedo is high (in snow, granite, or white sand areas, or 


over hayfields in summer) can produce severe radiation 
burns, skin cancers (very common in Australia), and 
temporary or longterm blindness. 

Plants, too, must be screened against sunburn by 
partial shade and by white paint on their stems in 
conditions of severe radiation (especially young plants). 
Older plants may suffer bark damage, but will survive. 

effects are best achieved by: 

• placing heat sources below storage and use 

• inducing cross-ventilation by building solar 
chimneys to draw in cool air; 

• actively fanning heated air to underfloor gravel 
storages where solar attics or trapped ceiling heat is 
the heat source; and 

• eliminating heat-induced condensation through 
the use of heat exchangers. 

• IN HEAT STOVES: Massive earth, brick, stone, or 
concrete heat storage masses must be insulated to retain 
heat that is otherwise lost by conduction to the ground, 
or by radiation to the exterior of houses. Conduction is 
prevented by solid foam or air-trap insulation (straw). 
Radiation loss is prevented by reflection from 
double-glazed windows, or reflective insulation 
hanging in air spaces. 

Reflective insulation doesn't work if it is dusty, dirty, 
or pressed against a conducting surface, hence it is of 
most use as free-hanging sheets, or ceiling sheets 
looped loosely across rafters. It can be kept clean (and 
effective) only in such situations as solar attics. Plain 
white paint is an excellent reflector for everyday use on 
walls or in concentrators. 

• PLANT CHOICE: AH plants with high biomass 
(e.g. trees) store heat in their mass (which is mainly 
water). Thus, fairly small clearings may be frost-free in 
cold climates. Dark evergreen trees absorb (and radiate) 
heat effectively; white-barked, shiny, or light-coloured 
trees reflect heat in cool districts, on forest edges, and 
where light itself is a limiting factor. 

• WATER AND STONE are good heat storages, 
having a high specific heat. Thus, bodies of water are 
good heat storages. Air has a low specific heat and is a 
very poor conductor of heat, hence a good insulator. 
Many insulation systems work simply by trapping air, 
or by being poor conductors (cork, sawdust, wood). 

These short examples, and some of the tabulated 
material, give the essential features of radiation that are 
applicable to everyday design. A preliminary design 
choice is to choose house sites for the maximisation of 
solar radiation in subtropical to cool climates and to 
shelter from radiation where excessive heat is a 
problem. Excess heat in one area of a house can be used 
in arid and tropical areas to "fuel" a cross- ventilation 
system, also essential in the humid tropics for cool dry 
air intake to the home. 

Designers should always be aware of opportunities to 
convert light to heat, to reflect more heat on to cool 
areas, to light dark areas by reflection or by skylight 

FIGURE 5.14 

Microhabitats develop due to combined sun and ram ellects 

placement, and to store heat below insulated slab 

_5 1 6_ 


Both wind and water transport can influence (by 
impendence or reflection) the quantity of light and heat 
on any site. Particles or molecules carried in air have a 
profound effect on available light, and heat can easily 
be transported about our system bv air and water, or by 
substances mixed in with them. 

Of all of these elements, we have least control of wind 
in terms of storage or generation, but we can control its 
behaviour on site by excluding, reducing, or increasing 
its force, using windbreak and wind funnels to do so. 

As a resident of a bare, cleared (once-forested) 
peninsula, when I speak of wind 1 know of what I 
write! The very table on which this book is penned 
rocks to gusts from the "roaring forties" and when the 
wind blows from the east, spicules of salt form on 
beards, clothes lines, and plants, burning off leaves and 
killing plant species; some hardy plants that withstand 
years of normal gales can die in salty summer winds. 

When it comes to crop, winds of 8 km/h are 
harmless. Those of 24 km/h reduce crop production 
and cause weight loss in animals, and at about 32-40 
km/h, sheer mechanical damage to plants exceeds all 
other effects; in fact, I have seen my zucchini uproot 
and bowl along like a tumbleweed. Trees are severely 
wind-pruned by a combination of mechanical damage 
and salt burn near coasts, and by the additional factor 
of sandblast in dunes (desert or coasts) and iceblast in 
cold climates. Wind transport of sands in deserts and 
incipient deserts buries fences, buildings, trees, and 

Although many sites are little affected by wind as a 
result of fortunate local conditions, or a general low 
level of wind effect in a region, very few coastal, island, 
sub-tropical or exposed hill sites can afford to ignore 
this factor. 

There are broad categories of wind speed and effect. 


just as there are for rainfall and temperature. The 
Beaufort Scale is the normal way to report winds, and 
equivalents are given in Table 5.5. 

More severe than mechanical damage are the minute 
sulphur and nitrogen particles carried by wind. In 
Colorado, Virginia, Utah, the Urals and in fact 
anywhere downwind of nuclear waste stores, tests, and 
accidents we can add plutonium and other radioactives 
to the wind factor. Dry sulphur, falling on leaf and soil, 
converts to acid in misty rains. On parts of the 
northeast coast of America and Canada, these rains can 
burn gardens and forests, or make holes in garments 
and tents in a few days. Near acid production factories, 
even paints and roofing are pitted and holed; this factor 
has become general in industrial areas and for many 
miles downwind. 

Windbreaks may mean the difference between some 
crop and a good crop, but in severe wind areas, the 
difference is more absolute and may mean that 
susceptible plants will produce no crop at all. Thus, a 

list of wind-tolerant (frontline- trees) is a critical list for 
food production and animal husbandry. 

Winds are fairly predictable and often bi-modal in their 
directions and effects in local areas. For the landscape 
designer, wind-flagging or older trees and wind- 
pruning tell the story; the site itself has summed total 
wind effects over time. 

From Latitudes 0° to 35° north and south in oceanic 
areas, winds will be bi-modal and seasonal, southeast 
or northwest in the southern hemisphere, southwest or 
northeast in the northern hemisphere. Locally, the 
directions will be modified by landscape, but the 
phenomena of windward and leeward coasts are almost 
universal. From Latitude 35° to the limits of occupied 
coasts, westerlies will prevail in winter, easterlies more 
sporadically as highs or lows pass over the site and 
remain stationary to the east or west. Cold winds will 








1 -3 

1 -5 

1 -3 

Light airs 





Light breeze 




8 - 12 

Gentle breeze 


11 -16 



Moderate breeze 





Fresh breeze 





Stormy breeze 





Near gale 







41 -47 



Strong gale 










Violent storm 


64 + 

118 + 

74 + 





Slight, no damage to crops or structures 



Mechanical damage to crops, some damage to structures — 

—| useiui energy 
—' produced 


Severe structural and crop damage. Damage to windmills. 


|Penetration (m) 

Reamlnlng Velocity (%) 






300- 1.500 

Neglible wind. 

TABLE 5.5 



blow from continental interiors in winter, and warmer 
but still chilling winter winds blow in from the seas. 

Islands and peninsulas from Latitudes 0° to 28° 
eperience two main wind modes, those of the winter 
winds or trade winds (southeast in the southern hemi¬ 
sphere, northeast in the northern hemisphere) and 
those of the monsoon. In effect, we look for two seasons 
of winds and two short periods of relative calms or 
shifting wind systems in these latitudes. These are the 
main winds of tropical oceanic islands. 

In summer, the cross-equatorial monsoon winds 
deflect to blow from the northwest in the southern 
hemisphere, and as southwest monsoons in the 
northern hemisphere. Southeast Asia and the Pacific or 
Indian ocean islands are most predictably affected by 
these bi-modal systems. Although many sites are also 
affected by only two main strong wind directions, these 
are rarely as strictly seasonal in effect as they are closer 
to the equator. 


On warm sea coasts, where onshore winds not only 
carry salt but also evaporate moisture, salt deposits on 
vegetation are the limiting factor on species selection, 
and only selected hardy species with fibrous or waxy 
surfaces can escape death or deformation by salt bum. 

As well as inorganic materials, w'ind may transport 
organisms ranging from almost impalpable spores of 
fungi and ferns to very weighty insects such as plague 
locusts which are swept aloft by heated air columns, 
and carried as frozen or chilled swarms to down¬ 
draught areas. Here, they thaw out and commence 
feeding, or perish in oceans far from land. Mosquitoes, 
fruit flies, wasps, and spiders deliberately spin aerial 
floatlines and also migrate over mountain and oceanic 
barriers on windstreams. Flocks of migrating birds also 
take advantage of windstreams as they circle the globe. 

Flow of air (wind) over leaf surfaces promotes rapid 
transpiration, as does high light intensity (Dauben- 
mire, 1974). When we have both effects together, shrubs 
and trees may lose too much water, and trees guard 
against this combined factor by presenting whitish 
undersides of leaves to the light as the wind blows, 
thus carrying on a dynamic balance between the light 
and wind factors. Vines and trees may alter leaf angles 
to reflect light, trap air, or to reduce the area of leaf 
exposed to light or wind. Thus, both pigmentation and 
leaf movement are used to balance the effects of 
variable incoming energy, and leaf pores close down to 
prevent moisture loss. 


In a radio programme on sailing (Australian Broad¬ 
casting Corporation, 19 Dec 84), Frank Bethwaite, a 
New Zealand-born Australian boat designer, pilot, and 
sailor outlined some of the characteristics of ground 
winds. Such winds do not blow steadily, but vary as 
gusts and calms in a predictable and locality-specific 

way; that is, the common winds of any one site have 
regular pulses. 

He states that such regular variations are easily 
timed; a 49-60 minute frequency of gusting is typical of 
mid-latitudes, with gusts 40% stronger than lulls. In 
lulls, the wind direction also changes, as light 
crosswinds at about 15° to the main wind direction. 

The variation in wind speed and direction is system¬ 
atic and regular, and both frequencies, durations, and 
amplitudes can be obtained by combinations of 
stopwatches, anemometers, and wind vanes (or all of 
these recorded on automatic equipment). 

Such "waves" of wind are made visible in grass-lands, 
or on the surface of waters viewed from a cliff. They are 
also, at times, reflected in clouds as "rank and file' 
systems. The lulls show as spaces between cloud ranks, 
and in these spaces, light clouds of different alignment 
represent the change of direction typical of lulls. 

The gusts are ponderous, representing vortices; the 
lulls are of light crosswinds. Some periods are short 
(Bahrain, 5.25 minutes; Sydney, fr-12 minutes; Toronto, 
10 minutes). Wave "fronts" on grasslands may come at 
every 14 seconds, with gusts at longer intervals. Sea 
waves themselves have a characteristic periodicity and 
speed, usually about 5-12 per minute, the period 
lengthening in storms. 

In the westerly wind belts, we can distinguish 
between the PREVALENT WINDS of from 8-24 km/h, 
which blow for five out of seven windy days, and the 
ENERGY WINDS of from 16-40 km/h which blow on 
the other two days. The energy winds come from 
between 15°-20° off the direction of the prevalent winds 
(Michael Hackleman, Wind and W indspinenrs, Peace 
Press, California. 1974). 


It is the chill factor—the removal of heat from surfaces, 
and evaporation of fluids—that creates cool to cold 
climates in the tropics at lower altitudes than adiabatic 
or altitude factors would indicate. This chill factor 
retards plant growth, and lowers the efficiency of solar 
devices and insulation. In cyclonic or hurricane areas, 
catastrophic winds may become the over-riding design 
modification, around which all other factors must be 

We are not much concerned with sheltered and low 
wind-energy sites, except to choose them for our 
dwellings in exposed landscapes, but close attention 
must be paid to shelter strategies in exposed sites. 

On sites with predictable wind patterns, revealed 
either by trees, derived from local knowledge, or 
indicated by wind records over time, we can plan 
directional, patterned windbreak of earthbank and 
trees. On sites where severe winds and sandblast may 
come from any direction (as in some deserts), the 
strategy is to impose a close rectangular or network 
pattern on windbreak. 

However the windbreaks are arranged, buildings, 
gardens, and animal shelters can be arranged to face the 

sun and benefit from solar impact. 

Essen tials of a Wind break 

The essentials of windbreak are fairly well known and 
local lists of species for windbreak are often available 
from forestry and agricultural advisors or departments. 
Essentials are: 

• Good species selection to be used as pioneers 
(easily grown); 

• Initial protection of planting from mechanical or 
wind damage (bagging, fencing); 

• Periodic or trickle irrigation to reduce desiccation; 

• Anchoring by stones or mulch; and 

• Species with 40-30% penetrability in the front line 
or as dominants. 

Many fire-resistant plants are also wind resistant, 
and in addition to these, some drought-resistant but 
fire-prone species (pines) will withstand wind. What 
they have in common are ways of resisting desiccation 
and sandblast. Such plants have, as common features: 

• Fibrous stems (palms). 

• Fleshy leaves (aloes, agaves. Euphorbias). 

• Hard, needle-like leaves or stems (pines, 
tamarisks, Casuarinas, some Acacias). 

• Furry or hairy (tomentose) leaf covers, or waxy 
leaves (Copmsma, eucalypts, some pines, some Acacias). 

Initial protection can come from: 

• Individual open-ended plastic bags around stakes 
(a common and effective establishment method). 

• Earth mounds, or side-cast earth banks of greater 
length than the tree line. 

• Brush fences, even wire-mesh fences, or staked 
fences with 40% wind penetrability. 

• Tussock or tough unmown grass to windward 
(leave if already present). 

All of these can be used in combination in very 
hostile areas. It is usual for the windward rows of trees 
to be heavily wind-flagged, and for taller species to be 
placed in their lee. On coasts and in deserts, it is not 
until after the fourth or even fifth tree row evolves that 
wind-prone fruit or nut-bearing trees will yield, so 
windbreak is the first priority for gardens in these 

Substantial trellis is a more immediate alternative, 
but care should be taken to make this sinuous (if of 
brick or mud brick) or zig-zagged (if of timber), as it 
has to withstand persistent and severe forces until 
shelter grows on either side of it. Earth mounds can be 
better streamlined, being less sensitive to windthrow. 
The hollow from which the earth is taken to make the 
mound can be made to hold water or to give protection 
to young plants. 

Tyre walls are sometimes feasible, and create great 
warmth inside the tyres, but are scarcely aesthetic 
unless very regularly arranged and planted. They have 
the advantage of being cheap, and can be removed once 
effective. Mesh fences, if stoutly built with a heavy top 
rail, can be the basis for fedges (fence-hedges) of 
thick-leaved vines, w hich on coasts may completely 
mound them over with tough semi-succulents such as 

Rh(igo>lia, Tetragonal, Carpobrotus, or Mesembryanthemuni. 
Rock walls and tyres may be similarly mounded with 
scramblers or cacti, some of which provide bee forage 


and berries or edible fruits. 

It is rare for tree canopies on dry saltwind coasts to 
gain more than 46 cm height in 1 m width (18 inches in 
3 feet), so considerable width must be given to pioneer 
windbreaks in these situations, unless those hardy 
pioneers such as the Norfolk Island pines can be nursed 
to grow to windward. However, as this slow climb to 
height commences from ground level, a fence, building, 
earth bank, or barrier gives it a great start for far less 
spread (Figure 5.15.D). 

Even a 46-62 cm (18-24 inch) high fence or mound 
earth will grow a sweet potato, strawberry, or cabbage 
in the lee, while hard-pruned canopies need not be 
barren, as many dwarf fruit, vine, and flower crops will 
grow below these if mulch and water are provided. In 
windbreak forests near coasts, small openings of 6-9 m 
(20-30 feet) provide garden shelter and admit light. 

There is, in fact, a special charm about those 3-3.5 m 
(10-12 feet) high dense coastal shrubberies in which 
nestle small shacks, through which wander sandy 
paths, and in which people create small patches of 
scattered garden using wastewater and mulch. Once 
shaped, fruit trees in this situation seldom need 
pruning, and at times one wonders if the wind is not an 
advantage in that it forces compact and careful work, 
punishes carelessness, and promotes wastewater use. 

Across the whole of the flattish peninsula of 
Kalaupapa on Moloka i, the Hawaiians had built tiny 
stone fences of 25-50 cm (10-20 inches) high and only 
4.5-5 m (15-18 feet) apart, behind which they grew a 
basic sweet-potato crop, and in which grew tough fern 
for mulch. All are now abandoned, but on the seaward 
coast, wild date somehow struggles to 4.5 m (15 feet) or 
so in the teeth of the tradewinds, and would have made 
a grand windbreak had the Hawaiians retained their 
land against tourism and graziers. Just to windward, 
the strong winds bring so much salt spray ashore that it 
crystalizes out in pinkish ponds, mixed inexorably with 
the red of the volcanic earth on which it forms. Even 
today, it is gathered as "Hawaiian salt", and is further 
mixed with the roasted kukui nut and chilies for a 
delicious raw-fish condiment. 

1. Shelterbtil effects on house design. For glazed areas and 
hot water (flat plate) collectors, wind chill factors 
remove 60% of heat alone. Shelterbelt (including thick 
vine trellis) around a house can effect a 20-30% saving 
in heating fuels in moderate to severe winters. Thus, in 
cold areas earthbanks plus shelterbelt, and a sun-facing 
aspect, is a critical design strategy. In deserts, where 
advected (wind-carried) heat is the most severe effect 
on human comfort, shelterbelt trees serve to reduce 
ground temperatures up to 15°C. 

2 . Effects of exposure on livestock. Blizzards will kill 
livestock and newborn lambs, and even hardy and 
adapted animals can lose 30% of their body weight in 3 
days of blizzard. As well as shelterbelts in fields, we 
need to be very careful to design fences so that they do 
not form downwind or downslope traps, as herds 

escaping blizzards will pile up against them and 
smother in fenced corners. All moorland and high 
plateau fences should allow easy downwind escape to 
wood lots, sheltered valleys, or lower elevations. 

In less severe conditions, sheep weight in unsheltered 
fields in New Zealand is 15% less than that of sheltered 
areas. Australia attributes 20% of all lamb losses to 
wind chill factors, and issues regular wind chill 
warnings at shearing time to prevent adult sheep loss. 

Cattle fed winter rations on exposed sites will eat 
16% less of this food, so that winter hay and 
concentrates need to be fed out in shelter for animals to 
obtain full benefit. Both heat and cold have similar 
effects on weight gain, and shelterbelt is one of the most 
effective ways of increasing livestock production, and 
conserving rations. Thus, in designing for livestock, 
fences, shelter, access to shelter, and feeding and 
watering points all need sensible placement, so that 
animals are not exposed to extreme temperatures. In the 
tropics and subtropics, a ridge planting of pines or 
Casuarinas with a wind gap left below the crowns 
affords both shade and an induced breeze that 
discourages flies and mosquitoes. Such ridges are also 
rich mulch sources for lower slopes. 

3. Civil construction. Snowdrift across highways is 
more effectively and permanently blocked by hedgerow 
of hardy Caragana and Eleagnus, which are estimated to 
be 50% cheaper than stout fences, and of course outlast 
them. Juniper in high country actually grows better in 
areas of snow drift (below the sharp ridges where snow 
forms cornices), and swales at such places enable more 
snow melt, therefore more available root moisture for 
trees in spring and summer. 

Wind shear on exposed highways or at caravan parks 
can cause casualties and property damage, so that we 
need to design windfast median strips and highway 
shelterbelt in areas of known hazard, but especially on 
mountain passes and near exposed coasts subject to 

4. Shelter in and around croplands and orchards. For 
croplands, a matrix of shelterbelt species 10-16 m in 
height and 33-66 m apart (Casuarina. poplar, 
Matsudana willow, trimmed eucalypt) affords wind 
protection for such crops as kiwifruit and avocado, and 
give the greatest increases in yield while reducing wind 
damage to fruit and leaf. For instance, citrus culled as 
damaged is 50% of the crop in unsheltered areas, versus 
18.5% in shelterbelt systems, cotton yields are 17.4% 
higher within five times the height of the shelterbelt, 
and fall off to a 7.9% advantage at ten times the height 
of the belt. 

Effects of shelterbelt are compound, and include 
more meltwater from snow, much greater fruit or seed 
set in bee-pollinated crop, the preservation of good 
shape in the trees, hence less pruning. Species selection 
of shelterbelt trees is essential, and a set of factors can 
be the criteria that assists the farm enterprise sheltered. 
These include: 

• Nitrogen fixation or good mulch potential from 
leaves and trimmings; 


• Hosting of predatory insects or birds that control 
crop pests; 

• Least moisture competition with crop (although 
roots from the shelterbelt can be ripped or trenched at 
the edge of crops); 

• Excellent forage yields or concentrated foods for 
livestock; and 

• Natural barriers to livestock (thorny plants, or 
woven hedge). 

Shelterbelt is planted as a succession from a tall grass 
to a taller legume to a long-term, tall, windfast hedge of 
e.g. Casuarina, poplar, willow, eucalypt, oak, chestnut. 
All this complex can be set out at once, and managed as 
it evolves to maturity. Quickset (by cuttings) hedges of 
poplar and Erythrina are popular because of their fast 
windbreak effect, but species must be chosen to suit a 
particular climate. 

Where space is ample and winds strong, the profile of 
a windbreak can be carefully streamlined, and up to six 
rows of tree and tall grass lines established, giving a 
mixed yield of forage, timber, fuel, mulch, honey, and 
shelter. In more constricted areas, a matrix of 
single-tree lines is usual, and effective if close-spaced. 
However, there is no such thing as a standard shape or 
windbreak, and very different configurations are 
needed for different sites, functions, and as accessory 
species to the enterprise sheltered, the wind strength, 
and the wind load (salt, sand, dust). 

5. Effects of windbreak on soil moisture. Windbreak is 
very effective in snowy areas, increasing soil moisture 
4% to four times the height of the break, and that to 1.2 
m depth in soils. Obviously, the benefits to trees in cold 
deserts are as a reserve of soil moisture that is rare in 
cold dry climates. The same effect occurs locally in the 
lee of tussock grasses, and can be used to establish a 

In foggy climates or facing sea coasts, we must add 
the effect of sea air condensation, which can be from 
80-300% of rainfall as leaf drip. In hot deserts and hot 
winds, the advected hot winds are the major factor in 
soil moisture loss. Such effects are produced over large 
treeless areas of dry grain crop as well as in deserts. 

The effects on grain crop of windburn and seed 
shattering in hot winds is insignificant for up to 18 
times the height of the windbreak. 

6. Less soil loss due to windstorms. Very serious soil 
losses of up to 100 T/ha/day in duststorm episodes 
(usually followed by torrential rain) are prevented by 
windbreak and soil pitting with tussock grasses. 
Approximately 50-70% of dusts settle out of the air 100 
m into tree clumps, so that treelines are the essential 
accompaniment to any pastoral or crop system in arid 

On coasts, removal of mangroves and coastal dune 
vegetation results in a sudden acceleration of wind 
erosion on beaches and coastal soils, and following 
deforestation, up to 30% more silt per annum flows into 
and reduces the useful life of water storages. 

7. Windbreak and hedgerow as accessory to crop and 
livestock. Quite apart from the above effects, windbreak 

species can be chosen to provide excellent crop mulch 
( Prosopis. Acacia, Erythrina, Melia, Canna) and fodders 
(all the foregoing species plus Leucaena, Fig, 
Pennisetum), and also to fix or recycle nitrogen and 
phosphatic fertilisers, or to mine trace elements 
(Casuarina, Banksia. Eucalyptus camaldulensis). 

Dry or cold-deciduous species and monsoon 
deciduous trees give a natural leaf fall in crop, 
automatically adding growth elements to the crop. In 
every crop and orchard it is advisable to interplant 
leguminous trees for mulch, soil building, and in-crop 
windbreak or frost cover. Trees like avocado and crops 
like papaya can be grown on sub-tropical frosty sites 
providing there is a high canopy of hardy palms or 
light-crowned legumes (e.g. Butia palm, Jacaranda, 
Tipuana tipu). Such sites do not frost, as there is no bare- 
ground radiation at night, and advected frost is 

Finally, forage and firewood from windbreak 
provides excess fuels to cook crop products, which is an 
important factor in the third world. In summary, 
well-chosen and designed windbreak can occupy up to 
30% of the total area of any site without reducing crop 
yields, and if windbreak species are chosen that aid the 
crop itself, there will be an increase in total yield, soil 
quality, and moisture available. 

rows and Shelterbelt s 

Shelterbelt species must be carefully selected to give 
multiple uses, to either ASSIST the crop yield, or ADD 
TO the end use yield (e.g. forage trees in pasture). This 
ensures the area occupied by shelterbelts adds to the 


total crop yields, rather than deducts from them. In 
general, we would gain in crop or pasture yield using 
nitrogen fixing and browse-edible shelterbelts species, 
and lose crop yield by using high water-demand, non- 
leguminous, and inedible shelterbelt species. 

However, where we experience severe sea or desert 
winds, which greatly reduce all yields, we must select 
salt-resistant or sand-blast-resistant windbreak no 
matter what the intrinsic yields of the shelterbelt. It is 
rare for sea-front trees to bear effectively (e.g. the outer 
4-5 rows of coconuts on exposed islands yield little 
crop), so that choice of frontline seacoast plants for seed 
or fruit yields is often irrelevant when considering 
species for multiple function. 

For isolated trees, or trees whose canopy lifts above 
the general forest level, wind of even low speeds may 
increase the transpiration rate, sometimes doubling 
water use. The effect is greatest on water-loving plants, 
and much less on dry-adapted species which have 
impermeable leaf cuticle and good control of stomata, 
or a cover of spines and hairs. 

Hot, dry winds, and winds laden with salt have the 
most damaging effect on plant yields (hence, animal 
yields), although at high wind speeds mechanical 
damage can occur, which prevents or reduces yields no 
matter what the humidity or salt content of the winds. 
Damaged crop plants such as com or bananas suffer 
photosynethic inefficiency ranging from 20-85% when 
the leaf laminae are tom or frayed, or the midribs are 
broken (Chang, 1968). 

Plants show different resistances to wind damage: 

• Wind tolerant (and wind-fast). These are the many 
short or creeping plants at the boundary layer of still air 
near the ground, or the front-line plants of sea coasts, 
e.g. Cerastium, Araucaria heterophylla Yields are little 
affected by strong winds. 

• Exposure tolerant , e.g. barley, some Brassicas, 
Casuarina and Coprosma repens. Yields are reduced in 
strong winds, but dry matter yield is less affected than 
in wind-sensitive plants. 

• Wind sensitive. These are the many important crops 

such as citrus, avocado, kiwifruit-vines, many 
deciduous fruits, corn, sugar cane, and bananas. Both 
plant height and yields rapidly decrease with increases 
in wind speed. For these species, very intensive 
shelterbelt systems are essential. 

Problems arise when the plants used for shelterbelt 
(e.g. poplar) are themselves heavy water-use species 
with invasive roots. An annual root-cutting or rip-line 
may be necessary along such windbreaks to permit the 
crop sheltered to obtain sufficient water, but it is best to 
choose more suitable species in the first place. 

Windbreak Height and Dens ity 

The height and density, or penetrability, of windbreak 
trees are the critical shelter-effect factors. Some 
configurations of windbelt may causes frost-pockets to 
develop in the still air of sheltered hollows. 
PERMEABILITY is an important factor if we want to 
reduce frost risk or to extend the windbreak effect 
(Figure 5.16). 

Briefly, we need windbreaks spread at no more than 20 
times the hedgerow height in any severe wind. In the 
establishment of wind-sensitive tree crop we may 
actually need continuous (interplant) windbreak. The 
length of windbreak needs to be greater than the length 
of the field protected, as wind funnels around the end 
of windbreaks in a regular flow pattern. 

Windbreak Configurations 

In general, species chosen for windbreak should permit 
40-70% of the wind through, which prevents the 
formation of a turbulent wind overturn on the leeward 
side. Windbreak height is ideally one-fifth of the space 
between windbreaks, but is still effective for low crop at 
one-thirtieth of the interspace. 

Sensible configurations are shown in Figure 5.18. 
Note that some wind shelter systems are placed 
throughout or within the crop or fruit area. 

A. Dense windbreak with bare stem area below. Effects : 
good summer cool shade for livestock; poor to useless 
winter shelter. Clumps of such trees on knolls allow 
animals to escape heat, and flies and mosquitoes are 
much reduced. 

, Pinus, Casuarina. 

B. Alternate (zig-zag) planting of very permeable 
trees. Effects : good "front-line" seafront systems to 
reduce salt burn and provide shelter for more dense 
trees on islands and coasts. Species : Araucaria, Pinus, 

C. Compound windbreak of high density. Effects : The 
best protection for eroding beaches, lifting the wind 
smoothly over the beach berm and trapping sand. Also 
effective in dust-storm areas as a dust trap. Species : 
Ground: Convulvulus. Phyla (Lippia), Mesembry- 
anthemum. Low shrubs: Echium fastuosum, wormwood. 
Shrubs: Coprosma repens. Trees: Lycitim. Cedrus. 
Cupressus, some plants. 


D. Permeable low hedgerow of Acacia or legumes. 
E ffects : Good effects on grass and crop growth, allows 
air movement to reduce frosts. Species : Acacia. 
Leucaena. Prosopis, Albizia. Glyricidia , tagasaste and like 
tree legumes. 

E. "Incrop "windbreak 

1: Savannah-style configuration of open-spaced 
light-crowned trees in crop or pasture. Effects : 
Excellent forage situation in arid areas, especially if 
trees provide fodder crop; pasture protected from 
drying winds. Species : Several fodder palms, Inga, 
Acacia, tagasaste, baobab, Prosopis. 

2: Complete or almost-complete crown cover in tree 
crop. Effects : Excellent frost-free sub-tropic and tropic 
lowland configuration where fruit trees (F) are 
interplanted with leguminous trees (L) as shelter and 
mulch, with Casuarhtas (C) as borders. Suited to humid 
climates, or irrigated areas. Species : Fruits (F) from 
palms, avocado, Inga, banana, citrus. Legumes (L) of 
tagasaste. Acacia, Albizia, Inga. Glyricidia, Leucaena. 
Borders (B) of Casuarina. low palms ( Phoenix 
canariensis), Leucaena. Prosopis. and other wind-fast trees 
and tall shrubs. 

The partial list of windbreak configurations given 
above covers only some cases, and in every case a de¬ 
signer must select species, study suitable total 
conformation, and allow for evolution or succession. As 
with all permaculture designs, general known 
principles are followed but every actual site will modify 
the design, as will the purposes for which shelter is 

Windbreak is essential for many crop yields, 
particularly in orchards. As discussed, wind causes 
mechanical damage, salt-burn, and may transfer 
(advect) heat and cold into the crop. Unless conditions 
are very severe, single-line windbreak spaced at 15 
times height may have a satisfactory effect on ground 
conditions, and this is recommended for crops and 
grasslands. However, severe montane and coastal 
winds need more careful design, and a complex 
windbreak of frontline species able to buffer the first 
onslaught of damaging winds is needed (Figure 5.19). 

For both tree crops and orchards, we have a very 
different potential strategy in that the windbreak may 
be composed of trees compatible with the protected 
forest or orchard system we wish to shelter, and can 
then be integral with the crop (Figure 5.18 El and E2). 
Great success with such strategies has been 
demonstrated both for wind and frost moderation in 
susceptible crop such as citrus, avocado and maca- 
damia nuts or chestnuts, using a protective interplant of 
hardy Acacia, Casuarina. Glyricidia. tagasaste, or 
Prosopis spaced within the crop. As all of the windbreak 
species mentioned fix nitrogen or phosphates, provide 
firewood, radiate heat, and shelter crop, it is sensible 
and beneficial to fully interplant any susceptible tree 
crops behind barriers of front-line windbreak. 
Windbreak in this instance is integral with the crop (as 

it is in natural forests). 

The importance of windbreak extends to SOIL 
CONSERVATION. In dry light soils, windbreaks can 
reduce dust and blown sand to 1/1000th of unsheltered 
situations (Chang, 1968) within 10 times the height of 
windbreak. Thus, in crops in arid or windy areas, it is 
necessary to plant windbreaks closer together for the 
sake of soil conservation. The loss of soil at 20 times 
windbreak height is 18 % of open situations, which is 
still too much when we can lose 8-40 t/ha in 

Similarly, WATER EVAPORATION can be halved in 
strong winds (32 km/h or more) for distances up to 10 
times height. Over 24 km/h, 30% gain in soil w’ater 
conservation is achieved. Only in still-air conditions is 
evaporation loss about the same for sheltered and open 
field conditions. 

SNOW MOISTURE is increased by a windbreak of 
type A or B (Figure 5.18) when the snow is trapped on 
fields. The snow depth in winter bears a close 
correlation to dry matter yields in spring and summer. 

FIGURE 5.19 

Two examples are given to suit straight-line fencing 
bowed towards the most damaging winds 

Crescents are 


FIGURE 5.18 


specific analysis Here. A suits ridges B tall vine crop. C coasts. D 
fields. El desert crops. E2 mesothermal orchards 

There is no 'best' windbreak; every crop. site, or condition needs 


so that crop yields are highest downwind from 
windbreak areas. Wherever snow blows across the 
landscape, windbreaks of savannah configurations 
create spring soil moisture traps. It is also possible to do 
this by using open swales in snow-drift areas. 
Windbreaks in exposed snowfield areas can be better 
established in the lee of earth bunds or in natural 
cornice just polewards of ridges. 

CROP YIELDS vary in increase from the 100% 
increase in such crops as avocado to 45% in corn, 
60-70% in alfalfa, 30% in wheat, and lesser gains 
(7-18%) for low crops such as lettuce. All these 
increases follow windbreak establishment on exposed 
sites. Effects are of course less in naturally sheltered 
situations or areas of normally low wind speed. 
However, almost all normal garden vegetables 
(cucurbit, tomato, potato) benefit greatly from wind 
shelter. For this reason, a ground pattern similar to that 
in Figure 5.20 is recommended for such crops and 
wind-affected pastures. 




i PA55£5 OUT 

FIGURE 5.20 '» 1 1 

The spiral pattern allows a continual tractor path; it also provides] 
a very sheltered crop environment tor all wind directions. 


Very stable and still-air calms near the equator may 
produce fierce updraughts of air over warm oceanic 

areas, which over some days or weeks build up to the 
great rising spirals of hurricanes. As these move slowly 
(usually at 24-32 km/h) across the ocean towards land, 
wind speeds around the vortex can reach 128-192 
km/h, while within the vortex itself a "tidal bulge" rises 
up to 2.7 m (9 feet) above sea level (Figure 5.21); this 
water bulge causes a tidal surge at coastlines. 

Vortices revolve anti-clockwise in the northern 
hemisphere, clockwise in the southern, and thus coastal 
areas to the north side have the highest water and wave 
levels in the northern hemisphere, and to the south side 
in the southern. The combined effects of rapidly 
fluctuating pressures, tidal bulge, wave and sea 
pile-up. and wave backwash create devastation on 
coasts. Although hurricanes cannot persist far inland, 
as the sea itself generates the vortex, the intense rains 
generated do reach well inland to flood rivers and 
estuaries, adding to the general destruction. With all 
effects combined in a "worst case" of high tides and 
prior rains, destructive wave attack can reach 6-9 m 
(20-30 feet) above normal high-tide wave levels. 

As wind strength increases at sea, wavelength also 
increases, so that normal wave fronts arriving at 8 per 
minute in calm Atlantic conditions slow down to a 
storm frequency of 5 per minute before great winds. 
These wider-spaced waves travel fast, are larger, and 
create severe backwash undermining of shorelines. 


Storm waves may therefore arrive long belore a 
cyclonic depression or hurricane, and the change of 
wave beat gives warning to the shore crabs, birds, fish. 

and turtles, who either take shelter inland or go to sea 
to escape the approaching hurricane. 

As modern satellite photographs are used to track the 
hurricane, there is usually a few days' warning for 
coastal areas, and evacuation is sometimes ordered. 
Well-built towns (such as Darwin, Australia, after its 
cyclonic devastation in 1972) can withstand cyclones 
with minimal damage, but such stoutness is usually 
only built in after an initial (and sometimes total) 
destruction. It is possible to strictly regulate and 
supervise buildings to be safe in hurricanes, and in 
areas where flimsy constructions are normal, to dig 
refuge trenches and caves for emergency shelter. All 
such shelter must be in well-drained hillside sites. 


Hurricanes are large, slow phenomena covering 
hundreds of square miles, and mainly confined to 
coasts facing large stretches of tropical seas, with very 
large heat cells. Tornadoes, however, may occur in quite 
cold inland areas, last only seconds or minutes, and 
affect only a few square kilometres. Thus, they usually 
escape detection by satellite and ground sensors. 

Nevertheless, the stresses placed on buildings, civil 
constructions, chemical or nuclear facilities, airfields 
and villages can be disastrous. Wind speeds may reach 
120 km/h, at worst 280 km/h; these speeds can exceed 
hurricane winds. The conditions for tornadoes are: 

• Thunderstorms with fast-growing cumulonimbus 

• A persistent source of warm moist air to feed the 
updraught side of the front; 

• An input of cold dry air entering the system from 
another direction; and 

• A vortex formation in the resulting storm; this 
reaches the ground as a tornado, caused by wind-shear 
effects at the border of the conflicting system, or as a 
frontal dust storm in deserts. 

Effects: Trees twisted off and broken; people and 


objects sucked out of cars and buildings; "rains' of soil, 
fish, frogs may fall out ahead of the disturbance. 


Intense wildfires (urban and rural) fanned by dry 
winds will create powerful vortices due to conditions 
very much like that of the tornado. The mass ignition of 
large areas of forests and buildings feed a powerful 
updraught. Colder dry air rushes in to replace the air 
consumed in burning, and fire tornadoes (firestorms) 
result, carrying large burning particles aloft on ’smoke 
nimbus" clouds. Whole house sections pinwheel across 
the sky to drop out ahead of the main fire front, where 
they in turn set up secondary firestorm conditions. The 
effects on people and property are very much like those 
of tornadoes, but with the additional danger of intense 

_ 5J _ 



Heat is transported on a world scale by two great 
circulations: that of the air masses, and those of oceanic 
currents. Of these, air masses are more wide-spread in 
their effect, and are least limited by land masses. 
Oceanic currents, or indeed proximity to any large body 
of water, have their greatest moderating effect on 
down-wind shorelines. Such effects may have little 
inland influence. The concept of continental climates 
was evolved to describe those extreme and widely 
fluctuating inland climatic zones that are not buffered 
by the effects of sea currents, and which demonstrate 
periods of extreme heat and cold, all the more marked 
on high mountains. 

Thus, the third complication on the simple 
temperature-rainfall classifications is CONT1NENT- 
AL1TY. After this, only one special factor remains, and 
it is the effect of hills or ranges of mountains on local 
climate; these effects are very like the latitudinal effects 
on a global scale. 


An average measure of temperature fall with altitude is: 
9.8°C/km (5.4°F/1000 feet) in rainless or dry air; or 
4-9°C/km (2.2-5°F/1000 feet) in humid and saturated 

As a rough approximation, every 100 m (330 feet) of 

altitude is equivalent to 1 ° of latitude, so that at 1000 m 
(3300 feet) on the equator, the temperatures are about 
equivalent to a climate 10° off the equator with the 
same humidity. At 10° latitude off the equator, a plateau 
at 1850 m (6000 feet) has a climate more like that at 30° 
latitude, with a probability of wind chill to below 
freezing. For high islands or ranges of mountains, this 
altitudinal factor is crucial to design strategies for 

homes and gardens. Altitude effect alone enables us to 
grow a wide range of plant species on a high island, 
using the area from ocean to mountain- top. 

High Aljitude^Fffects 

Mountains are not in fact strictly "latitude equivalents", 
as the air is more rarefied, air pressure less, and 
radiation therefore higher. On very high mountains of 
4000 m (13,000 feet) and more, people may experience 
oxygen deficiency (mountain sickness), snow or 
radiation blindness, and suffer from the extremes of 
day-night temperature fluctuations. The mountain 
sickness of oxygen stress is not felt by locals, but can 
cause extreme fatigue, insomnia, and laboured 


£A£L.y r\ofO*NC< 




FIGURE 5.25 


These follow a daily cycle Many bird species use these winds to 
follow a daily migration (downhill at dawn, to ridge forests at evening). 
Both wind and temperature effects are local 

breathing in visitors. In the Peruvian Andes, day 
temperatures remain at 16-19°C (61-66°F) all year, but 
night temperatures fall rapidly to -10°C (14°F). Shade 
temperatures are lower than at sea level, due to the less 
effective heat transfer and insulation effects of the 
rarefied air. Water boils at lower temperatures due to 
the low atmospheric pressure, and snow may sublime 
directly to water vapour rather than melting. High 
mountains reduce the range of foods available. 

Snow cover may serve as an insulating blanket, and 
prevent early spring thawing, or even autumn freezing 
if it covers unfrozen ground. Snow cover also causes 
intense reflection, and raises air temperatures just 
above the snow by day. At night, radiation from snow 
causes an extremely cold ground air layer, so that any 
plants protruding from snow suffer these extremes of 
diurnal temperature. 

As great as the effect of altitude is, the effect of slope 
is even more pronounced. Daubenmire (1974) records 
that slopes of 5° towards the poles "reduce soil 
temperatures as much as 168 km distance" towards the 
poles, so that even a gentle slope away from the sun 
creates very much cooler conditions locally. The effect 
of cold ravines in near-permanent shadow is extreme 
indeed, and one may stand in hot sunlight in the 
Himalayas and gaze into icy depths where only the 
hardiest life forms exist, and where ice may 
permanently cover rocks and spray zones caused by 
waterfalls or rapids. 


We have referred to the chill of narrow, shaded, high 
altitude gorges, but an opposite effect occurs in 
sun-facing wider valleys, sheltered from winds. Here, 
hot air builds up rapidly, soils are drier, and strong 
winds may be generated (upslope and up valley by day, 
downslope and down valley at night). Figure 5.25 
demonstrates this effect in moderate mountain areas of 

3,000-4,000 m (9,850-13,000 feel). 

In large valleys, and especially in cool moist climates, 
the upslope wind may result in the generation of a 
chain of cumulus clouds at the valley head, trailing off 
as a succession of clouds from mid-morning to 
evening. In more tropical humid climates, the cloud 
may be continuously held on the mountain tops; this 
forms part of the standing cloud of high islands. Such 
cloud (and rainfall) effects are accentuated by forest on 
the valley sides and ridges, as trees actively humidify 
the air streams by transpiration in hot weather. 

Valleys in tundra and desert support tree populations 
absent from the plain or peneplain areas surrounding 
them, but the reasons may differ in that tundra valleys 
are likely to be protected by (driven) deep snow cover. 
This preserves warm or sub-lethal soil temperatures in 
winter (as well as providing excess summer melt 
moisture). Valleys in deserts remain moist due to the 
deep detritus which fills their floors; the shaded soils 
lose less moisture to evaporation. Lethal soil 
temperatures are also avoided by partial shading. Both 
ice-blast and sand-blast are modified or absent in 
valley floors, so that unprotected seedlings can survive 
high winds in the shelter of valleys. 

Thus, valleys (or wadis) are preferred growing sites 
in deserts, and provide tree products in otherwise 
treeless tundras, although the latter sites are rarely 
occupied by human settlement. 

In the field, we often notice a sudden coldness just 
before dawn in valley areas; this is the time of the 
greatest depth of cold air, and hence the greatest 
intensity of cold. Air flowing down from the mountains 
has pooled all night, and just before the sun rises, we 
(and many animals) are at our greatest exposure and 
lowest ebb. It is at this time that winds off glaciers 
flowing down cold valleys reach their maximum speed. 

Without wind or air flow, radiation frost can form, as 
it does in sheltered hollows and tree clearings. In these 
areas, opening up the clearings or draining them of cold 
air may help reduce frost, if that is the aim (Figure 

When, some years ago, I grew such crops as tomatoes 
and cucurbits inside open tree canopies, I did prevent 
frost, but lost crop due to low light levels and a lack of 
wind or insect pollination. In such cases, a shade-side 
screen of reflector plants facing the sun would help to 
keep light levels up, and plants to attract bees need to 
be placed around the clearing. Arboreal or ground 
browsers within forests are also worrisome in gardens 
(possum and porcupine for example). Green-leaf 
vegetables, however, are not usually eaten, and can be 
successfully grown in small forest clearings or in open 
forest in frosty areas. 

_5 1 8_ 


Despite the weak light and short growing season at 

high (sub-polar) latitudes, the very long summer days 
provide more than a sufficient quantity of light for 
vigorous plant growth. The daily total for late summer 
(July) is 440 Langleys at Madras, India (13°N); 680 
Langleys at Fresno, California (36°N); 450 at Fairbanks, 
Alaska (64°N). The average radiation in temperate areas 
is 1-5 times that of the tropics (Chang, 1968). 

This is accentuated, on or near coasts, by the 
moderate temperatures from the convection of air over 
warm currents in such areas as Alaska and the 
northwest coastal regions of Europe. The benefit of 
these areas is that the generally lower temperatures, 
which suit photosynthesis, confer a photosynthetic 
efficiency that makes a considerable production of 
cereal, berries, tomatoes, potatoes, and vegetable crops 
tolerant of short season/long day conditions. The often 
deep periglacial soils provide the basis for the 
production of gigantic lettuce, cabbage, spinaches. and 
root crops, so that these areas are very favourable for 
agriculture in summer. 

Such conditions prevail in Alaska, Ireland, Scotland, 
and parts of Norway. Shelter and added nutrients from 
seaweeds and manures yield rich meadows and heavy 
vegetable production during the long summer days. 
The small stone-walled fields of Ireland produce 
abundant sweet hay, root crops, and greens for storage 
during winter. 

Conversely, the ample light at low (equatorial) 
latitudes is inefficient due to the extremely high 
temperatures there, and the excess light may mean that 
plants are light saturated. Photosynthesis may actually 
decline in the intense light, and the energy built into the 
plants may be less in sunlight than in partial shade. 
Shade (down to a level of 20% sunlight) is of great 
benefit in tropical deserts and sunny equatorial 
climates. Trials of shadecloth with 50-70% light 
transmission may greatly increase plant bulk and 
production, e.g. of sugar beet, thus the importance of 
tree shade and shadecloth in deserts and cleared-area 

Similarly, temperatures above 25°C (77°F) sharply 
decrease photosynthetic efficiency, so that the normal 
desert or equatorial condition of high light and 
temperature is very inefficient for the production of 
plant material. In the arctic or high latitudes, 15°C 
(59°F) is optimum for adapted species and cultivars, and 
20-24°C (68-75°F) for many useful food plants. Tropics 
are noted for a low production of those crops which can 
be also grown in temperate areas; light shade may be 
the essential component for increased yields. 

In bright sunlight, leaf temperatures often exceed air 
temperatures, so that the diffuse light of overcast or 
cloudy days in high latitudes helps plant growth, 
especially after midday as temperatures would then 
also rise above optimum in direct sunlight. 

Photosynethetic efficiency is limited by the ability of 
the leaf to obtain carbon dioxide or by low levels of 
available carbon dioxide. At high light intensity, we 
need to supply carbon dioxide (to the saturation level 
of 0.13% to obtain a 2-3 times increase in photosyn- 


thetic rate. Carbon dioxide can be supplied by 
composting or by housing animals in greenhouses 
where light is more than sufficient. 

It follows that the summer periods of the high 
latitudes are ideal for biomass production, while 
equatorial regions evolve biomass mainly as a result of 
a year-round (inefficient) growth and perennial crops. 
The ideal of steady low light/low temperature 
conditions may be at times achieved below the closed 
forests of tropical mountains, but these sites are very 
limited in extent, and carbon dioxide concentration is 
also low. Rice, for example, yields 4-5 times better in 
temperate areas than in tropical ones, although up to 
three crops per year in the tropics helps to increase local 
yields over the year. 

It should be feasible to assist tropical crop yields by 
spacing permeable-crowned trees throughout crops to 
reduce both light and temperature, e.g. using Prosopi s 
trees with millet crops in India, or partially-shading 
taro in Hawaii. Grass growth in temperate areas also 
increases with shelterbelt, but this may reflect the 
warmer conditions and lack of mechanical wind damage 
that such trees as tagasaste provide. Trials of 
light-transmitting or thin-crowned palms and legume 
trees would quickly show results, and there are a good 
many observations to suggest that (if water is sufficient) 
crops under leguminous trees do much better in the 
tropics than a crop standing on its own. 

Part of the problem in tropics (both for biomass 
production and nutrition) is that non-adapted 
temperate crops are persistently grown there. True 
tropical plants can not only stand much higher levels of 
light before saturation, but can also maintain 
photosynthesis at low ( 0 . 10 %) carbon dioxide. 

In summary, we do not have to accept the climatic 
factors of a site as unchangeable any more than we do 
its treelessness or state of soil erosion. By sensible 
placement of our design components, we can create 
myriad small differences in local climatic effects on any 
site. In the technical field, we can create useful 
conversions of energy from incoming energy fluxes 
such as wind and sun, and produce energy for the site. 
In the patterning of a site with trees, ponds, earth 
systems, or hedgerows, we can actively moderate for 
better climatic conditions, or to eliminate some local 
limiting factor. 

_5 I 9_ 


Chang, Jen-Hu, Climate ami Agriculture, Aldine Pub. 
Co.. Chicago, 1968. 

Chorley, R J. (ed.). Water, Earth, and Man, Methuen & 
Co., London, 1969. 

Cox, George W., and Michael D. Atkins, Agricultural 
Ecology, W. H. Freeman & Co., San Francisco, 1979. 

Daubenmire, Rexford F., Plants and Environment, Wiley 
International, 1974. 

Eyre, S. R., World Vegetation Patterns, Macmillan, 
London, 1971. 

Gaskell, T. F., Physics of the Earth, World of Science 
Library, Thames & Hudson, London, 1970. 

Geiger, Rudolf, The Climate Near the Ground, Harvard 
University Press, 1965. 

Holford, Ingrid, Interpreting the Weather, David & 
Charles, Newton Abbot, UK. 

lames, P. E., Outline of Geography, Ginn & Co.. Boston, 

Trewartha, S. T., An Introduction to Climate, McGrawHill, 
New York, 1954. 

Twidale, C. R., Structural Landforms, Australian 
National University Press, Canberra, Australia. 

Staff of the L. H. Bailey Hortorium, Cornell University, 
Hortus Third: a concise dictionary of the plants cultivated in 
the United States and Canada, Macmillan Publishing Co., 

_5 1 10_ 


Check data on average rainfall, temperature, and wind 
speed and direction for the region (often found by 
contacting the Bureau of Meteorology). 

Ascertain the general "hardiness"’ zone for plants and 
animals. This is based on temperature, with frost being 
the limiting factor. Make a survey of the plants that 
grow in the area, noting special circumstances 
surrounding plants that are "marginal"; what is the 
technique or microclimate that allows them to grow? 

Find out about flood locations and periodicity, rain 
intensity, temperature extremes, and the seasonal rainfall 
pattern. Allow for extremes (e.g. no rain in summer) 
when designing. 

Consider total precipitation (snow, hail, rain, fog, 
condensation, and dew) so that your design can include 
ways to trap and store moisture (dry climates) or ways 
to dispose of too much moisture (wet climates). 

Consider light aiHiilability, especially on foggy coasts; 
light becomes the limiting factor for flowering plants. 

Continental climates mean more temperature 
extremes, while maritime climates buffer severe heat or 

Altitude effects: approximately every 100 m of 
altitude is equivalent to 1 ° of latitude, so that a variety 
of plants can be grown if the property contains hills and 
flats. In the sub-tropics, even temperate-area plants can 


be grown on high islands or hills. 

Note where frost is produced (in hollows, on flats, 
and in large clearings) and where it is absent (the 
"thermal belt" on hills, under tree canopies). 

Note tree flagging on the site; this shows the direction 
of persistent winds (although winds, sometimes severe, 
may blow from other directions). You can put tall stakes 
with coloured cloth or plastic streamers at different 
locations and observe them seasonally. (Figure 6.2). 

For accurate temperatures, you can have several 
maximum/minimum thermometers in different 
locations. These thermometers record the highest and 
lowest temperatures reached during 24 hours, and are 
helpful in locating microclimatic areas such as thermal 
belts (if on a sun-facing slope), cold drainage areas, 
frost hollows. 

Site house and garden on the thermal belt if possible. 

In minimal-frost areas, plant light-canopy trees in the 
garden for frost protection (tree canopies help keep 
rapid cooling of the earth to a minimum). Or plant into 
a steep-sided clearing or pit. 

In houses, design so that you use light and radiation 
to best effect, particularly in temperate climates. 
Particular use should be made of the thermosiphon 
effect of heat, so that heat sources are placed below 
storage and use points. 

Use the principle that white reflects, dark absorbs, 
heat. Plant shrubs and trees needing heat and light in 
front of white-painted walls. 

When planning windbreaks, consider: 

• Trees that give multiple function, e.g. mulch 
iCasuanna), bee nectar (dogwood), sugar pods for 
animals (carob, honey locust), edible leaves ( Ixucaena , 
tagasaste), berries for poultry (Copwsma repens , Russian 

• The windbreak planting itself may need initial 
protecion and care (nutrients, water, weeding, or 

• If the winds are very severe, look around the area to 
see what stands up to it, and plant it whether it 
provides multiple function or not. Plant more useful 
plants in its lee. Protection includes fencing, earth 
banks, tyre walls, etc. 

• Choose a windbreak configuration that is effective 
for the particular design situation. In tropical and 
subtropical areas, a thin-crowned windbreak in crop 
can be used to advantage, providing shade and mulch 
for vegetable crop. 


Chapter 6 


On the dry island of Hierro in the Canary Islands, 
there is a legend of the rain tree: a giant Til* tree 
(Ocotea foelens). "... the leaves of which condensed 
the mountain mists and caused water to drip into 
two large cisterns which were placed beneath. The 
tree was destroyed in a storm in 1612 A.D. but 
the site is known, and the remnants of the cistern 
preserved ... {This one treel distilled sufficient 
water from the sea mists to meet the needs of all 
the inhabitants." 

(David Bramwell) 

For me. trees have always been the most pene¬ 
trating teachers. 1 revere them when they live in 
tribes and families, in forests and groves... They 
struggle with all the forces of their lives for one 
thing only: to fulfill themselves according to their 
own laws, to build up their own forms, to 
represent themselves. Nothing is holier, nothing is 
more exemplary, than a beautiful strong tree. 

(Herman Hesse. Trees ', Natural Resources 

Journal, Spring 1980) 

1 am astonished to find whole books on the func¬ 
tioning of trees which make no mention of their 
splendid mechanical and aerodynamic perform¬ 

(Vogel, Life in Moving Fluids. 1981) 

A point which is often overlooked is the effect of 
trees in increasing the total precipitation 
considerably beyond that recorded by rain gauges. 
A large proportion of the rime which collects on 
the twigs of trees in frosts afterwards reaches the 
ground as water, and. in climates such as those of 
the British Isles, the total amount of water 
deposited on the twigs from fogs and drifting 
clouds is considerable, and most of it reaches the 

streams or underground storage, or at least re¬ 
places losses from subsequent rainfall. 

Of more importance, however, to hydraulic 
engineers is the effect of woodlands in modifying 
the run-off. The rush of water from bare hillsides 
is exchanged for the slower delivery from the 
matted carpet of the woodland, losses by evapora¬ 
tion may be much diminished and the melting of 
snow usefully retarded. In catchments from which 
flood waters are largely lost, woodlands may 
increase the available runoff by extending the 
period of surface flow. The maximum floods of 
rivers are reduced, and the lowest summer flow 
increased. Woodlands are usually much more 
effective than minor vegetation, such as gorse and 
heather, in preventing the soil from being carried 
from the land into an open reservoir. 

To protect a reservoir from silting. It may be 
unnecessary to plant large areas, the silt being 
arrested by suitable planting of narrow belts of 
woodland, or by the protection of natural growth, 
along the margins of the streams. 

Some engineers consider that in the case of 
small reservoirs the shelter afforded by a belt of 
trees along the margins is of value In reducing the 
amount of scour of the banks caused by wave 
action. Afforestation over considerable areas In 
large river basins would, in many cases, reduce 
the amount of silting in navigable rivers and 

A matter which does not receive sufficient 
attention in connection with hydraulic engineer¬ 
ing Is the effect of Judicious planting or woodland 
conservation over small areas. A narrow belt of 
woodland along the foot of a slope will arrest the 
soil brought down by rains from the hillside. The 
encouragement of dense vegetation along the 
bottom of a narrow valley may check the rate of 
ilood discharge to a useful extent. The planting of 


suitable trees along ridges and for a little way 
down the slope facing the rain bearing and damp 
winds, will produce the maximum of certain 
desired effects, in proportion to the area occupied. 
Suitable tree and bush growths in swampy areas 
and around their margins will Increase their effect 
in checking flood discharge, and may prevent 
these areas from contributing large quantities of 
silt to the streams during very heavy rains. Areas 
of soft, cultivable soil liable to denudation may 
similarly be protected. Generally, a country which 
is. In the ordinary English sense of the words, 
well timbered' is. from the point of view of the 
hydraulic engineer, a favourable country; and in 
the development of new lands the future effects 
of a poposed agricultural policy should be 
considered from this point of view, and in 
consultation with hydraulic engineers. 

(R.A. Ryves, Engineering Handbook, 1936) 

_6 1 1_ 


This chapter deals with the complex interactions 
between trees and the incoming energies of radiation, 
precipitation, and the winds or gaseous envelope of 
earth. The energy transactions between trees and their 
physical environment defy precise measurement as 
they vary from hour to hour, and according to the 
composition and age of forests, but we can study the 
broad effects. 

What 1 hope to show is the immense value of trees to 
the biosphere. We must deplore the rapacity of those 
who, for an ephemeral profit in dollars, would cut trees 
for newsprint, packaging, and other temporary uses. 
When we cut forests, we must pay for the end cost in 
drought, water loss, nutrient loss, and salted soils. Such 
costs are not charged by uncaring or corrupted 
governments, and deforestation has therefore 
impoverished whole nations. The process continues 
with acid rain as a more modem problem, not charged 
against the cost of electricity or motor vehicles, but with 
the inevitable account building up so that no nation can 
pay, in the end, for rehabilitation. 

The "capitalist”, "communist", and "developing" 
worlds will all be equally brought down by forest loss. 
Those barren political or religious ideologies which fail 
to care for forests carry their own destruction as lethal 
seeds within their fabric. 

We should not be deceived by the propaganda that 
promises "for every tree cut down, a tree planted". The 
exchange of a 50 g seedling for a forest giant of 50-100 
tonnes is like the offer of a mouse for an elephant. No 
new reafforestation can replace an old forest in energy 
value, and even this lip service is omitted in the 
"cut-and-run" forestry practised in Brazil and the 
tropics of Oceania. 

The planting of trees can assuredly increase local 

precipitation, and can help reverse the effects of 
dryland soil salting. There is evidence everywhere, in 
literature and in the field, that the great body of the 
forest is in very active energy transaction with the 
whole environment. To even begin to understand, we 
must deal with themes within themes, and try to follow 
a single rainstorm or airstream through its interaction 
with the forest. 

A young forest or tree doesn't behave like the same 
entity in age; it may be more or less frost-hardy, 
wind-fast, salt-tolerant, drought-resistant or shade 
tolerant at different ages and seasons. But let us at least 
try to see just how- the forest works, by taking one 
theme at a time. While this segmented approach leads 
to further understanding, we must keep in mind that 
everything is connected, and any one factor affects all 
other parts of the system. I can never see the forest as 
an assembly of plant and animal species, but rather as a 
single body with differing cells, organs, and functions. 
Can the orchid exist without the tree that supports it, or 
the wasp that fertilises it? Can the forest extend its 
borders and occupy grasslands without the pigeon that 
carries its berries away to germinate elsewhere? 

Trees are, for the earth, the ultimate translators and 
moderators of incoming energy. At the crown of the 
forest, and within its canopy, the vast energies of 
sunlight, wind, and precipitation are being modified for 
life and growth. Trees not only build but conserve the 
soils, shielding them from the impact of raindrops and 
the desiccation of wind and sun. If we could only 
understand what a tree does for us, how beneficial it is 
to life on earth, we would (as many tribes have done) 
revere all trees as brothers and sisters. 

In this chapter, I hope to show that the little we do 
know has this ultimate meaning; without trees, we 
cannot inhabit the earth. Without trees we rapidly create 
deserts and drought, and the evidence for this is before 
our eyes. Without trees, the atmosphere will alter its 
composition, and life support systems will fail. 

_ 6 I 2 _ 


A tree is, broadly speaking, many biomass zones. These 
are the stem and crown (the visible tree), the detritus 
and humus (the tree at the soil surface boundary) and 
the roots and root associates (the underground tree). 

Like all living things, a tree has shed its weight many 
times over to earth and air, and has built much of the 
soil it stands in. Not only the crown, but also the roots, 
die and shed their wastes to earth. The living tree 
stands in a zone of decomposition, much of it 
transferred, reborn, transported, or reincarnated into 
grasses, bacteria, fungus, insect life, birds, and 

Many of these tree-lives "belong with" the tree, and 
still function as part of it. When a blue jay, currawong, 
or squirrel buries an acorn (and usually recovers only 


80% as a result of divine forgetfulness), it acts as the 
agent of the oak. When the squirrel or wallaby digs up 
the columella of the fungal tree root associates, guided 
to these by a garlic-like smell, they swallow the spores, 
activate them enzymatically, and deposit them again to 
invest the roots of another tree or sapling with its 
energy translator. 

The root fungi intercede with water, soil, and 
atmosphere to manufacture cell nutrients for the tree, 
while myriad insects carry out summer pruning, 
decompose the surplus leaves, and activate essential 
soil bacteria for the tree to use for nutrient flow. The 
rain of insect faeces may be crucial to forest and prairie 

What part of this assembly is the tree? Which is the 
body or entity of the system, and which the part? An 
Australian Aborigine might give them all the same 
’’skin name", so that a certain shrub, the fire that 
germinates the shrub, and the wallaby that feeds off it 
are all called warn, although each part also has its name. 
The Hawaiians name each part of the taro plant 
differently, from its child or shoot, to its nodes and 

It is a clever person indeed who can separate the total 
body of the tree into mineral, plant, animal, detritus, 
and life! This separation is for simple minds; the tree 
can be understood only as its total entity which, like 
ours, reaches out into all things. Animals are the 
messengers of the tree, and trees the gardens of 
animals. Life depends upon life. All forces, all elements, 
all life forms are the biomass of the tree. 

A large tree has from 10,000 to 100,000 growing 
points or MERISTEMS, and each is capable of 
individual mutation. Unlike mammals, trees produce 
their seed from multitudinous flowers. Evidence is 
accumulating that any one main branch can therefore 
be an "individual" genetically. Some deciduous poplars 
may produce a single evergreen branch. 'Seedlessness' 
in fruit, or a specific ripening time, may belong only to 
one branch. Grafts and cuttings perpetuate these 
isolated characteristics, so we must look upon the tree 
itself as a collection of compatible genetic individuals, 
each with a set of persistent characteristics which may 
differ from place to place on the tree, and each of which 
may respond differently to energy and other stimuli. 
Like ourselves, trees are a cooperative amalgam of 
many individuals; some of these are of the tree body, 
but most are free-living agents. As little as we now 
know about trees, they stand as a witness to the 
complex totality of all life forms. 



Vogel (1981) notes that as wind speed increases, the 
tree's leaves and branches deform so that the tree 
steadily reduces its exposed leaf area. At times of very 
high winds (in excess of 32 m/sec) the interception of 

light, efficient water use, and convective heat 
dissipation by the tree becomes secondary to its 

Vogel also notes that very heavy and rigid trees 
spread wide root mats, and may rely more totally on 
their weight, withstanding considerable wind force 
with no more attachment than that necessary to prevent 
slide, while other trees insert gnarled roots deep in rock 
crevices, and are literally anchored to the ground. 

The forest bends and sways, each species with its 
own amplitude. Special wood cells are created to bear 
the tension and compression, and the trees on the edge 
of a copse or forest are thick and sturdy. If we tether a 
tree halfway up, it stops thickening below the tether, 
and grows in diameter only above the fixed point. Some 
leaves twist and reverse, showing a white underside to 
the wind, thus reflecting light energy and replacing it 
with kinetic or wind energy. In most cases, these 
strikingly light-coloured leaves are found only in forest 
edge species, and are absent or uncommon within the 

As streamlines converge over trees or hills, air speed 
increases. Density and heat may also increase, resulting 
in fast low-pressure air. To leeward of the obstruction, 
such streamlines diverge, and an area of slower flow, 
higher pressure, and cooler air may result. If rain has 
fallen due to the compression of streamlines, however, 
the latent heat of evaporation is released in the air, and 
this drier air can be warmer than the air mass rising 
over the obstruction. The pressure differentials caused 
by uplift and descent may affect evaporation as much 
as wind drying or heat. 

Apart from moisture, the wind may carry heavy 
loads of ice, dust, or sand. Strand trees (palms, pines, 
and Casuiirinas) have tough stems or thick bark to 
withstand wind particle blast. Even tussock grasses 
slow the wind and cause dust loads to settle out. In the 
edges of forests and behind beaches, tree lines may 
accumulate a mound of driven particles just within 
their canopy. The forest removes very fine dusts and 
industrial aerosols from the airstream within a few 
hundred metres. 

Forests provide a nutrient net for materials blown by 
wind, or gathered by birds that forage from its edges. 
Migrating salmon in rivers die in the headwaters after 
spawning, and many thousands of tons of fish remains 
are deposited by birds and other predators in the 
forests surrounding these rivers. In addition to these 
nutrient sources, trees actively mine the base rock and 
soils for minerals. 

The effect of the wind on trees is assessed as the 
Griggs and Putnam index (Table 6.1), and the 
accompanying deformations in both crown shapes and 
growth (as revealed in stems) is given a value which is 
matched to wind speeds with an average 17% accuracy. 

Such scales and field indicators are of great use in 
design. When we go to any site, we can look at the 
condition of older trees, which are the best guide to 
gauge wind effect. Trees indicate the local wind 
direction and intensity, and from these indicators we 




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No deformations of branches 

can place windbreak to reduce heat loss in homes, to 
avoid damage in catastrophic winds, and to steer the 
winds to well-placed wind machines. 

TABLE 6.1 



V (m/sec.) 






3.3 - 4.2 

7.5 - 9.5 





5.2 - 6.2 



6.3 - 7.5 






8.6- 11 





[From Wade. John E.. and Wendell Hewson. 1979. Trees as 
indicators ot wind power potential. Dept of Atmospheric 
Sciences. Oregon State University.) 

__ 6 I 4 _ 


EVAPORATION causes heat loss locally and 
CONDENSATION causes heat gain locally. Both effects 
may be used to heat or cool air or surfaces. The USDA's 
Yearbook of Agriculture on Trees (1949) has this to say 
about the evaporative effects of trees: "An ordinary elm, 
of medium size, will get rid of 15,000 pounds of water 
on a clear dry hot day" and "Evapotranspiration (in a 40 
inch rainfall) is generally not less than 15 inches per 

Thus, the evaporation by day off trees cools air in hot 
weather, while the night condensation of atmospheric 
water warms the surrounding air. Moisture will not 
condense unless it finds a surface to condense on. 
Leaves provide this surface, as well as contact cooling. 
Leaf surfaces are likely to be cooler than other objects at 
evening due to the evaporation from leaf stomata by 
day. As air is also rising over trees, some vertical lift 
cooling occurs, the two combining to condense 
moisture on the forest. We find that leaves are 86% 
water, thus having twice the specific heat of soil, 
remaining cooler than the soil by day and warmer at 
night. Plants generally may be 15°C or so warmer than 
the surrounding air temperature. 

Small open water storages or tree clumps upwind of 
a house have a pleasant moderating effect. Air passing 
over open water is cooled in summer. It is warmed and 
has moisture added even in winter. Only water 
captured by trees, however, has a DEHUMIDIFYING 
effect in hot and humid tropical areas, as trees are 
capable of reducing humidity by direct absorption 
except in the most extreme conditions. 

Reddish-coloured leaves, such as are developed in 
some vines and shrubs, reflect chiefly red light rays. 

Sharp decreases in temperature may result by 
interposing reddish foliage between a thermometer and 
the sun, up to 20°C (36°F) lower than with green 
pigmented plants (Daubenmire, 1974). Whitish plants 
such as wormwood and birch may reflect 85% of in¬ 
coming light, whereas the dark leaves of shade plants 
may reflect as little as 2%. It follows that white or 
red-coloured roof vines over tiles may effectively lower 
summer temperatures within buildings or in trellis 
systems. Additional cooling is effected by fitting fine 
water sprays and damp mulch systems under trellis, 
thus creating a cool area of dense air by evaporation. 
This effect is of great use in moderating summer heat in 
buildings, and for providing cool air sources to draw 
from by induced cross-ventifilation. 

_ ^5 _ 


Trees have helped to create both our soils and 
atmosphere. The first by mechanical (root pressure) and 
chemical (humic acid) breakdown of rock, adding life 
processes as humus and myriad decomposers. The 
second by gaseous exchange, establishing and 
maintaining an oxygenated atmosphere and an active 
water-vapour cycle essential to life. 

The composition of the atmosphere is the result of 
reactive processes, and forests may be doing about 80 % 
of the work, with the rest due to oceanic or aquatic 
exchange. Many cities, and most deforested areas such 
as Greece, no longer produce the oxygen they use. 

The basic effects of trees on water vapour and 
windstreams are: 

• Compression of streamlines, and induced 
turbulence in air flows; 

• Condensation phenomena, especially at night; 
Rehumidification by the cycling of water to air; 

• Snow and meltwater effects; and 

• Provison of nucleii for rain. 

We can deal with each of these in turn (realizing that 
they also interact). 

Windstreams flow across a forest. The streamlines that 
impinge on the forest edge are partly deflected over the 
forest (almost 60 % of the air) and partly absorbed into 
the trees (about 40% of the air). Within 1000 m (3,300 
feet) the air entering the forest, with its tonnages of 
water and dust, is brought to a standstill. The forest has 
swallowed these great energies, and the result is an 
almost imperceptible warming of the air within the 
forest, a generally increased humidity in the trees 
(averaging 15-18% higher than the ambient air), and air 
in which no dust is detectable. 

Under the forest canopy, negative ions produced by 
life processes cause dust particles (++) to clump or 
adhere each to the other, and a fall-out of dispersed 


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dust results. At the forest edge, thick-stemmed and 
specially wind-adapted trees buffer the front-line 
attack of the wind. If we cut a windward forest edge, 
and remove these defences, windburn by salt, dust 
abrasion, or just plain windforce may well lull or throw 
down the inner forest of weaker stems and less resistant 
species. This is a commonly observed phenomenon, 
which I have called "edge break". Conversely, we can 
set up a forest by planting tough, resistant trees as 
windbreak, and so protect subsequent downwind 
plantings. Forest edges are therefore to be regarded as 
essential and permanent protection and should never be 
cut or removed. 

If dry hot air enters the forest, it is shaded, cooled, 
and humidified. If cold humid air enters the forest, it is 
warmed, dehumidified, and slowly released via the 
crown of the trees. We may see this warm humid air as 
misty spirals ascending from the forest. The trees 
modify extremes of heat and humidity to a life- 
enhancing and tolerable level. 

The winds deflected over the forest cause 
compression in the streamlines of the wind, an effect 
extending to twenty times the tree height, so that a 12 m 
(40foot) high line of trees compresses the air to 244 m 
(800 feet) above, thus creating more water vapour per 
unit volume, and also cooling the ascending air stream. 
Both conditions are conducive to rain. 

As these effects occur at the forest EDGE, a single 
hedgerow of 40% permeability will cause similar 

compression. In flat country, and especially in the path 
of onshore winds, fine grid placements of rain gauges 
in such countries as Holland and Sweden reveal that 
40% of the rainfall measured down-wind of trees and 
mounds 12 m (40 feet) or more in height is caused by 
this compression phenomena. If wind speeds are higher 
(32 km/h or more), the streamlines may be preserved, 
and rain falls perpendicular to the windbreak. 
However, at lower wind speeds (the normal winds), 
turbulence and overturn occurs. 

Wind streaming over the hedgerow or forest edge 
describes a spiral section, repeated 58 times downwind, 
so that a series of compression fronts, this time parallel 
to the windbreak, are created in the atmosphere. This 
phenomena was first described by Ekman for the 
compression fronts created over waves at sea. 

The Ekman spirals over trees or bluffs may result in a 
ranked series of clouds, often very regular in their rows. 
They are not perfectly in line ahead, but are deflected 
by drag and the Coriolus force to change the wind 
direction, so that the wind after the hedgerow may 
blow 5-15 degrees off the previous course. (One can 
imagine that ranks of hedgerows placed to take 
advantage of this effect would eventually bring the 
wind around in a great ground spiral.) 

Winds at sea do in fact form great circuses, and bring 
cyclonic rains to the westerly oceanic coasts of all 
continents. These cyclones themselves create warm and 
cold fronts which ridge up air masses to create rain. In 
total, hedgerows across wind systems have a profound 
effect on the airstreams passing over them, and a sub¬ 
sequent effect on local climate and rainfall. 

On the sea-facing coasts of islands and continents, the 
relatively warmer land surface creates quiet inshore 
airflows towards evening, and in many areas cooler 


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ice nudeii. inducers ol stream line compression, and re-bumiditiers 
ol the airstream create most ol the conditions that create 

water-laden air flows inland. Where this humid air 
flows over the rapidly cooling surfaces of glass, metal, 
rocks, or the thin laminae of leaves, condensation 
occurs, and droplets of water form. On leaves, this may 
be greatly aided by the colonies of bacteria 
(Pseudomonas) which also serve as nucleii for frost 
crystals to settle on leaves. 

These saturated airstreams produce seaward-facing 
mosses and lichens on the rocks of fresh basalt flows, 
but more importantly condense in trees to create a 
copious soft condensation which, in such conditions, 
may far exceed the precipitation caused by rainfall. 
Condensation drip can be as high as 80-86% of total 
precipitation of the upland slopes of islands or sea 
coasts, and eventually produces the dense rainforests of 
Tasmania, Chile, Hawaii, Washington/Oregon, and 
Scandinavia. It produced the redwood forests of 
California and the giant laurel forests of pre-conquest 
Canary Islands (now an arid area due to almost 
complete deforestation by the Spanish). 

A single tree such as a giant Til (Ocotea foetens) may 
present 16 ha of laminate leaf surface to the sea air, and 
there can be 100 or so such trees per surface hectare, so 
that trees enormously magnify the available 
condensation surface. The taller the trees, as for 
example the giant redwoods and white pines, the larger 
the volume of moist air intercepted, and the greater the 
precipitation that follows. 

All types of trees act as condensers; examples are 
Canary Island pines, laurels, holm oaks, redwoods, 
eucalypts, and Oregon pines. Evergreens work all year, 
but even deciduous trees catch moisture in winter. Who 
has not stood under a great tree which "rains" softly 
and continuously at night, on a clear and cloudless 
evening? Some gardens, created in these conditions, 
quietly catch their own water while neighbours suffer 

The effects of condensation of trees can be quickly 
destroyed. Felling of the forests causes rivers to dry up, 
swamps to evaporate, shallow water to dry out, and 
drought to grip the land. All this can occur in the 
lifetime of a person. 

Precipitation from clear air is much less than that 
from fog, from which the precipitation by condensa¬ 
tion often exceeds the local rainfall. Advection fogs are 
most noticeable where cold currents such as the Oya 
Shio off East Asia and the Labrador current off 
northeast America cause humid inland airstreams in 
spring and summer. Southfacing coasts near 
Newfound-land get 158 days of fog per year. Wherever 
mountains or their foothills face onshore night winds, 
fog condensation will probably exceed rainfall. On 
Table Mountain (South Africa) and on Lanai (Hawaii), 
fog drip has been measured at 130-330 cm, and in both 
cases condensation exceeds rainfall. Redwoods in 
California were once restricted to the fog belt, but will 
grow well in areas of higher rainfall without fogs 



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(Chang, 1968). In Sweden "... wooded hills rising only 
3050 m (9,500 feet) above the surrounding plains may 
cause precipitation Irain onlyl during cyclonic spells 
(fronts! to be increased by 50-80% compared with 
average falls over the lowland." In most countries, 
however, the rain gauge net is too coarse to detect such 
small variations (Chorley and Berry, 1971). 

If it rains again, and again, the clouds that move inland 
carry water mostly evaporated from forests, and less 
and less water evaporated from the sea. Forests are 
cloud-makers both from water vapour evaporated from 
the leaves by day, and water transpired as part of life 
processes. On high islands, standing clouds cap the 
forested peaks, but disappear if the forests are cut. The 
great bridging cloud that reached from the forests of 
Maui to the island of Kahoolawe, remembered by the 
fathers of the present Hawaiian settlers, has 
disappeared as cutting and cattle destroyed the upper 
forests on Maui and so lifted the cloud cap from 
Kahoolawe, leaving this lower island naked to the sun. 
With the cloud forests gone, and the rivers dry, 
Kahoolawe is a true desert island, now used as a 
bombing range for the U.S. Air Force. 

A large evergreen tree such as Eucalyptus globulus 
may pump out 3,600-4,500 1 of water a day, which is 
how Mussolini pumped dry the Pontine marshes of 
Italy. With sixty or so of these trees to the hectare, many 
tens of thousands of litres of water are returned to the 
air to become clouds. 

A forest can return (unlike the sea) 75% of its water to 
air, "in large enough amounts to form new rain clouds." 
(Bayard Webster, "Forests' Role in Weather Documented 
in Amazon", New York Times (Science Section), 5 July 
’83). Forested areas return ten times as much moisture 
as bare ground, and twice as much as grasslands. In 
fact, as far as the atmosphere itself is concerned, "the 
release of water from trees and other plants accounts 
for half, or even more, of all moisture returned to air." 
(Webster, ibid.) This is a critical finding that adds even 
more data to the relationship of desertification by 

It is data that no government can ignore. Drought in 
one area may relate directly to deforestation in an 
upwind direction. This study "clearly shows that 
natural vegetation must play an important role in the 
forming of weather patterns" (quote from Thomas E. 
Lovejoy, Vice-president of Science, World Wildlife 

Clouds form above forests, and such clouds are now 
mixtures of oceanic and forest water vapour, clearly 
distinguishable by careful isotope analysis. The water 
vapour from forests contain more organic nucleii and 
plant nutrients than does the "pure" oceanic water. 
Oxygen isotopes are measured to determine the forests’ 
contribution, which can be done for any cloud system. 

Of the 75% of water returned by trees to air, 25% is 
evaporated from leaf surfaces, and 50% transpired. The 

remaining 25% of rainfall infiltrates the soil and 
eventually reaches the streams. The Amazon discharges 
44% of all rain falling, thus the remainder is either 
locked into the forest tissue or returns to air. Moreover, 
over the forests, twice as much rain falls than is available 
from the incoming air, so that the forest is continually 
recycling water to air and rain, producing 50% of its 
own rain (Webster, ibid.). These findings forever put an 
end to the fallacy that trees and weather are unrelated. 

Vogel (1981), applying the "principle of continuity" of 
fluids to a tree, calculates that sap may rise, in a young 
oak. fifty times as fast as the leaves transpire (needing 
only 7% of the total trunk area as conductive tissue, 
with an actual sap speed of 1 cm/sec). It is thus certain 
that only perhaps one-fiftieth of the xylem is 
conducting sap upwards at any one time, and that most 
xylem cells contain either air or sap at standstill. Per¬ 
haps too, the tree moves water up in pulsed stages 
rather than as a universal or continuous streamflow. 

With such rapid sap flows, however, we can easily 
imagine the water recycled to atmosphere by a large 
tree, or a clump of smaller trees. 

It is a wonder to me that we have any water available 
after we cut the forests, or any soil. There are dozens of 
case histories in modern and ancient times of such 
desiccation as we find on the Canary Islands following 
deforestation, where rivers once ran and springs 
flowed. Design strategies are obvious and urgent—save 
all forest that remains, and plant trees for increased 
condensation on the hills that face the sea. 

Although trees intercept some snow, the effect of shrubs 
and trees is to entrap snow at the edges of clumps, and 
hold 75-95% of snowfall in shade. Melting is delayed 
for 210 days compared with bare ground, so that release 
of snowmelt is a more gradual process. Of the trapped 
snow within trees, most is melted, while on open 
ground snow may sublime directly to air. Thus, the 
beneficial effects of trees on high slopes is not confined 
to humid coasts. On high cold uplands such as we find 
in the continental interiors of the U.S.A. or Turkey near 
Mt. Ararat, the thin skeins of winter snow either blow- 
off the bald uplands, to disappear in w-armer air, or else 
they sublime directly to water vapour in the bright sun 
of winter. In neither case does the snow melt to 
groundwater, but is gone without productive effect, and 
no streams result on the lower slopes. 

Even a thin belt of trees entraps large quantities of 
driven snow in drifts. The result is a protracted release 
of meltwater to river sources in the highlands, and 
stream-flow at lower altitudes. When the forests were 
cleared for mine timber in 1846 at Pyramid Lake, 
Nevada, the streams ceased to flow, and the lake levels 
fell. Add to this effect that of river diversion and 
irrigation, and w'hole lakes rich with fish and waterfowl 
have become dustbow-ls, as has Lake Winnemucca. The 
Cuiuidika’a Indians (Paiute) who live there lost their 
fish, waterfowl, and freshwater in less than 100 years. 


The cowboys have won the day, but ruined the future to 
do so. 

The upward spirals of humid air coming up from the 
forest carry insects, pollen, and bacteria aloft. This is 
best seen as flights of gulls, swifts and ibis spiralling up 
with the warm air and actively catching insects lifted 
from the forest; their gastric pellets consist of insect 
remains. It is these organic aerial particles (pollen, leaf 
dust, and bacteria mainly) that create the nucleii for 

The violent hailstorms that plague Kenya tea 
plantings may well be caused by tea dust stirred up by 
the local winds and the feet of pickers, and "once above 
the ground the particles are easily drawn up into 
thunderheads to help form the hailstorms that bombard 
the tea-growing areas in astounding numbers... Kenyan 
organic tea leaf litter caused water to freeze in a test 
chamber at only -5°C, in comparison with freezing 
points of -11°C for eucalyptus grove leaf litter, and -8°C 
for the litter from the local indigenous forests" (of 
Colorado). That is, tea litter "is a much better 
seeding-agent than silver iodide, which requires -8°C 
to -10°C to seed clouds." (New Scientist, 22 Mar 79). 
Thus, the materials given up by vegetation may be a 
critical factor in the rainfall inland from forests. 

All of these factors are clear enough for any person to 
understand. To doubt the connection between forests 
and the water cycle is to doubt that milk flows from the 
breast of the mother, which is just the analogy given to 
water by tribal peoples. Trees were "the hair of the 
earth" which caught the mists and made the rivers flow. 
Such metaphors are clear allegorical guides to sensible 
conduct, and caused the Hawaiians (who had 
themselves brought on earlier environmental 
catastrophes) to "tabu" forest cutting or even to make 
tracks on high slopes, and to place mountain trees in a 
sacred or protected category. Now that we begin to 
understand the reasons for these beliefs, we could 
ourselves look on trees as our essential companions, 
giving us all the needs of life, and deserving of our care 
and respect. 

It is our strategies on-site that make water a scarce or 
plentiful resource. To start with, we must examine ways 
to increase local precipitation. Unless there is absolutely 
no free water in the air and earth about us (and there 
always is some), we can usually increase it on-site. 
Here are some basic strategies of water capture from 

• We can cool the air by shade or by providing cold 
surfaces for it to flow over, using trees and shrubs, or 
metals, including glass. 

• We can cool air by forcing it to higher altitudes, by 
providing windbreaks, or providing updraughts from 
heated or bare surfaces (large concreted areas), or by 
mechanical means (big industrial fans). 

• We can provide condensation nucleii for raindrops 
to form on, from pollen, bacteria, and organic particles. 

• We can compress air to make water more plentiful 
per unit volume of air, by forcing streamlines to 
converge over trees and objects, or forcing turbulent 
flow in airstreams (Ekman spirals). 

If by any strategy we can cool air, and provide 
suitable condensation surfaces or nucleii, we can 
increase precipitation locally. Trees, especially 
crosswind belts of tall trees, meet all of these criteria in 
one integrated system. They also store water for local 
climatic modification. Thus we can clearly see trees as a 
strategy for creating more water for local use. 

In summary, we do not need to accept "rainfall” as 
having everything to do with total local precipitation, 
especially if we live within 30-100 km of coasts (as 
much of the world does), and we do not need to accept 
that total precipitation cannot be changed (in either 
direction) by our action and designs on site. 

_ 6 I 6 _ 


Rain falls, and many tons of rain may impact on earth 
in an hour or so. On bare soils and thinly spaced or 
cultivated crop, the impact of droplets carries away soil, 
and may typically remove 80 t/ha, or up to 1,000 
tonnes in extreme downpours. When we bare the soil, 
we lose the earth. 

Water run-off and pan evaporation, estimated as 
80-90% of all rain falling on Australia, carries off 
nutrients and silt to the sea or to inland basins. As we 
clear the land, run-off increases and for a while this 
pleases people, who see their dams fill quickly. But the 
dams will silt up and the river eventually cease to flow, 
and the clearing of forests will result in flood and 
drought, not a long-regulated and steady supply of 
clean water. 

When rain falls on a forest, a complex process begins. 
Firstly, the tree canopy shelters and nullifies the impact 
effect of raindrops, reducing the rain to a thin mist 
below the canopy, even in the most torrential showers. 
There is slight measurable silt loss from mature forests, 
exceeded by the creation of soils by forests. 

If the rain is light, little of it penetrates beyond the 
canopy, but a film of water spreads across the leaves 
and stems, and is trapped there by surface tension. The 
cells of the tree absorb what is needed, and the 
remainder evaporates to air. Where no rain penetrates 
through the canopy, this effect is termed "total 
interception". INTERCEPTION is the amount of rain¬ 
fall caught in the crown. It is the most important 
primary effect of trees or forests on rain. The degree of 
interception is most influenced by these factors: 

• Crown thickness; 

• Crown density; 

• Season; 

• Intensity of rain; and 

• Evaporation after rain. 


Broadly speaking, interception commonly falls 
between 10-15% of total rainfall. Least interception 
occurs in thinned and deciduous forests, winter rain, 
heavy showers, and cloudy weather conditions, when it 
is as little as 10% of rain. Most interception occurs with 
dense, evergreen trees, light summer rain, and sunny 
conditions, when it may reach 100 % of the total. 

However, if more rain falls, or heavy rains impact on 
the trees, water commences to drift as mists or droplets 
to earth. This water is called THROUGHFALL. 
Throughfall depends on the intensity of rain, and there 
is little interception effect in heavy downpours. As an 
average figure, the throughfall is 85% of rain in humid 

At this point, throughfall is no longer just rainwater, 
any more than your bathwater is rainwater; throughfall 
contains many plant cells and nutrients, and is in fact a 
much richer brew than rainwater. Dissolved salts, 
organic content, dust, and plant exudates are included 
in the water of throughfall (Table 6.2). "The results 
show that rain washes large amounts of potassium and 
smaller amounts of nitrogen, phosphorus, calcium, and 
magnesium from the canopies to the surface soil. Utter 
adds organic matter, and is a rich source of calcium and 
nitrogen and a moderately rich source of magnesium 
and potassium." (Murray, J. S. and Mitchell, A., Red 
Gum and the Nutrient Balance, Soil Conservation 

Authority, Victoria, Australia, undated). 

Nor can throughfall be measured in rain gauges, for 
the trees often provide special receptors, conduits, and 
storages for such water. The random fall of rain is 
converted into well-directed patterns of flow that serve 
the needs and growth in the forest. In the stem bases of 
palms, plantains, and many ephiphytes, or the flanged 
roots of Terminalia trees and figs, water is held as aerial 
ponds, often rich in algae and mosquitoes. Stem mosses 
and epiphytes absorb many times their bulk of water, 
and the tree itself directs water via insloping branches 
and fissured bark to its tap roots, with spiders catching 
their share on webs, and fungi soaking up what they 
need. Some trees trail weeping branches to direct 
throughfall to their fibrous peripheral roots. 

With the aerial resevoirs filled, the throughfall now 
enters the humus layer of the forest, which can itself 
(like a great blotter) absorb 1 cm of rain for every 3 cm 
of depth. In old beech forests, this humus blanket is at 
least 40 cm deep, and the earth below is a mass of 
fungal hyphae. In unisturbed rainforest, deep mosses 
may carpet the forest floor. So, for 40-60 cm depth, the 
throughfall is absorbed by the decomposers and living 
systems of the humus layer. Again, the composition of 
the water changes, picking up humic exudates, and 
water from deep forests and bogs may then take on a 
clear golden colour, rather like tea. 

TABLE 6.2 --- 

Nutrient content ot litter, canopy drip, and ram in the open ol a naturally regenerating stand ol red gum < Eucalyptus camaldulensis). Gringegalgona. 
VIC, Australia. (Source Murray, J S . and A Mitchell. Red Gum and the Nutrient Balance. Soil Conservation Authority. Australia (undated)). 






RN (LB/A.) 


RAIN (in.) 








Old trees; 

[5% of Total) 































(95% of Total) 

























34 0 






















Cavendish § 








* 1:5/5/60 - 4/5/61. ‘2: 22/11/60 - 4/5/61. 

*3:1/9/55 - 1/9/56. 

4:1/9/54 - 1/9/55. 

§ From Hutton and Leslie (1958). 


Not Determined. 




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Every tree, every plant species, intercedes in ram to change the 

composition, energy, and distribution of water; the overall eflect of 
trees is to moderate and conserve incoming energy. 


pH can reach as low as 3.5 or 4.0 from natural humic 
layers, and rivers run like clear coffee to sea. Below the 
humus lies the tree roots, each clothed in fungal hyphae 
and the gels secreted by bacterial colonies. 30-40% of 
the bulk of the tree itself lies in the soil; most of this 
extends over many acres, with thousands of kilometres 
of root hairs lying mat-like in the upper 60 cm of soil 
(only 10-12% of the root mass lies below this depth but 
the remaining roots penetrate as much as 40 m deep in 
the rocks below). 

The root mat actively absorbs the solution that water 
has become, transporting it up the tree again to 
transpire to air. Some dryland plant roots build up a 
damp soil surround, and may be storing surplus water 
in the earth for daytime use; this water is held in the 
root associates as gels. Centrosema and Gleditsb both are 
dryland woody legumes which have "wet" root zones, 
and other plants are also reported to do the same in 
desert soils ( Prosopis spp.) 

The soil particles around the tree are now wetted 
with a surface film of water, as were the leaves and root 
hairs. This bound water forms a film available to roots, 
which can remove the water down to 15 atmospheres 
of pressure, when the soil retains the last thin film. 
Once soil is fully charged (at "field capacity"), free 
water at last percolates through the interstitial spaces 
of the soil and commences a slow progression to the 
streams, and thence to sea. 

At any time, trees may intercept and draw on these 
underground reserves for growth, and pump the water 
again to air. If we imagine the visible (above-ground) 
forest as water (and all but about 5-10% of this mass is 
water), and then imagine the water contained in soil, 
humus, and root material, the forests represent great 
lakes of actively managed and actively recycled water. 
No other storage system is so beneficial, or results in so 
much useful growth, although fairly shallow ponds are 
also valuable productive landscape. 

At the crown, forceful raindrops are broken up and 
scattered, often to mist or coalesced into small 
bark-fissured streams, and so descend to earth robbed 
of the kinetic energy that destroys the soil mantle 
outside forests. Further impedence takes place on the 
forest floor, where roots, litter, logs, and leaves redirect, 
slow down, and pool the water. 

Thus, in the forest, the soil mantle has every 
opportunity to act as a major storage. As even poor 
soils store water, the soil itself is an immense potential 
water storage. INFILTRATION to this storage along 
roots and through litter is maximised in forests. The soil 
has several storages: 

• RETENTION STORAGE: as a film of water bound 
to the soil particles, held by surface tension. 

• INTERSTITIAL STORAGE: as water-filled cavities 
between soil particles. 

• HUMUS STORAGE: as swollen mycorrhizal and 
spongy detritus in the humic content of soils. 

A lesser storage is as chemically-bound water in 
combination with minerals in the soil. 

As a generalisation, 2.5-7 cm (1-3 inches) of rain is 

stored per 30 cm (12 inches) depth of soil mantle in 
retention storage, although soils of fine texture and 
high organic content may store 10-30 cm (4-12 inches) 
of rain per 30 cm depth. In addition, 0-5 cm (0-2 inches) 
may be stored as interstitial storage. 

Thus the soil becomes an impediment to water 
movement, and the free (interstitial) water can take as 
long as 1-40 years to percolate through to streams. 
Greatly alleviating droughts, it also recharges the 
retention storages on the way. Thus, it almost seems as 
though the purpose of the forests is to give soil time 
and means to hold fresh water on land. This is, of 
course, good for the forests themselves, and enables 
them to draw on water reserves between periods of 
rain. (Odum, 1974). 

_6 .7 _ 


Let us now be clear about how trees affect total 
precipitation. The case taken is where winds blow 
inland from an ocean or large lake: 

1. The water in the air is that evaporated from the 
surface of the sea or lake. It contains a few salt particles 
but is clean". A small proportion may fall as rain 
(15-20%), but most of this water is CONDENSED out of 
clear night air or fogs by the cool surfaces of leaves 
(80-85% ). Of this condensate, 15% evaporates by day 
and 50% is transpired. The rest enters the groundwater. 
Thus, trees are responsible for wore uniter in streams than 
the rainfall alone provides. 

2. Of the rain that falls, 25% again re-evaporates 
from crown leaves, and 50% is transpired. This 
moisture is added to clouds, which are now at least 50% 
"tree water". These clouds travel on inland to rain again. 
Thus trees may double or multiply rainfall itself by this 
process, which can be repeated many times over 
extensive forested plains or foothills. 

3. As the air rises inland, the precipitation and 
condensation increases, and moss forests plus standing 
clouds may form in mountains, adding considerably to 
total precipitation and infiltration to the lower slopes 
and streams. 

4. Whenever winds pass over tree lines or forest 
edges of 12 m (40 feet) or more in height, Ekman spirals 
develop, adding 40% or so to rainfall in bands which 
roughly parallel the tree lines. 

5. Within the forest, 40% of the incident air mass may 
enter and either lose water or be rehumidified. 

6. And, in every case, rain is more likely to fall as a 
result or organic particles forming nucleii for 
condensation, whereas industrial aerosols are too small 
to cause rain and instead produce dry, cloudy 

Thus, if we clear the forest, what is left but dust? 


_ 6 I 8 _ 


Chang, Jenhu, Climate and Agriculture, Aldine Pub. Co., 
Chicago, 1968. 

Daubenmire, Rexford F.. Plants and Environment: a 
textbook of plant aulecology, Wiley & Sons, N. Y., 1974. 

Geiger, Rudolf, The Climate Near the Ground, Harvard 
University Press, 1975. 

Odum, Eugene, Fundamentals of Ecology , W. B. 

Saunders, London, 1974. 

Plate, E. )., The Aerodynamics of Shelterbells, Agricultural 
Meteorology 8,1970. 

U. S. Department of Agriculture, Trees, USDA Yearbook 
of Agriculture, 1949. 

Vogel, Stephen, Life in Moving Fluids, Willard Grant 
Press, Boston, 1981 


Chapter 7 


Water is the driving force of all nature. 
(Leonardo da Vinci) 

In an animal or a plant. 99 molecules In 100 are 
water... An organism is a pool in a stream of water 
along which metabolites and energy move through 

(W.V. Macfarlane) 

The sustained flow of rivers is truly remarkable, 
considering that precipitation is an unusual event 
in most areas of the earth. Localisation of pre¬ 
cipitation in space or time is striking |e.g. at Paris. 
It rains for 577 hours a year, or only 7% of the 
time. B.Molllson |. Few storms last more than a few 
hours, so that even storm days are mainly 
rainless. Yet rivers now throughout the year. The 
sustaining source of flow is effluent ground- 
water... The amount of soil water is about fifteen 
times the amount In channel storage in rivers. 

(Nace in Chorley, 1969) 

_ 7A _ 


Very little of the world s total water reserves are 
actually available for present human needs. Many areas 
of earth, particularly dryland areas, over-developed 
cities, and towns or cities surrounded by polluting 
industry and agriculture, face an absolute shortage of 
useable water Millions of city-dwellers now purchase 
water, at prices (from 1984 on) equivalent to or greater 
than that of refined petroleum. This is why the value of 
land must, in future, be assessed on its yield of potable 
water. Those property-owners with a constant source 

of pure water already have an economically-valuable 
'product" from their land, and need look no further for 
a source of income. Water as a commodity is already 
being transported by sea on a global scale. 

ing a cropland property to develop, should be an 
adequate, preferably well-distributed, and above all 
reliable rainfall. "Adequate" here is about a minimum of 
80 cm (31 inches) and upwards. An equally important 
factor is the ability of the area to hold water as dams in 
clay or clay-loam storages; any stream flow within the 
boundaries is a bonus. All other factors (soil type, 
present uses, number of titles, market potential, access, 
and forested areas) are secondary to water availability. 

Little of the lands now used for crop agriculture have 
such fortunate characteristics. Few farmers have 
invested in "drought-proofing" their land by creating 
gravity-fed irrigation systems of Keyline systems iS> . 
Specific strategies of water conservation and control are 
given in this book under their appropriate climatic and 
landform sections. 

While there are no economically-feasible strategies or 
technologies for freshwater creation from the sea or 
from polluted sources, there are several currently 
neglected strategies for recycling, purification, 
conservation, and increased storages of rainwater. In 
particular, the construction of tanks and dams have 
been neglected in built-up areas, as have earth storages 
on farms and in rural areas. Waste usage ranging from 
over-irrigation, non-recycling in industry, inappropri¬ 
ate domestic appliances, and unnecessary uses (on 
lawns and car washes) have not as yet been adequately 
costed by legislators or by householders. 

Tables 7.1 and 7.2 show abstract figures of the global 
and local water cycles. These should not be regarded as 
fixed or even sufficient representations of water in 
relation to actively designed or rehabilitated 
landscapes. There are ways in which we can 
constructively reverse past trends in water deficits. 


waste, pollution, and misuse. There is plenty of water 
for the world if we define the ways in which we store 
and use it carefully. 

_ 72 _ 



Silver iodide, and no doubt other ice nucleii such as tea 
dust can be "seeded" into cumulus, cumulonimbus, or 
nimbostratus clouds (by plane, ground burners, or 
rocket) in order to initiate local precipitation. 

Until recently these attempts to make rain were 
assessed as ineffective because no one had, at the time, 
realised how far and for how long the seeding effects 
spread and persisted. More recent analysis show that 
rain in fact increases over a very wide area, and that 
secondary effects last for months, so that varying wind 
directions and speeds carry the induced rain effects for 
hundreds or thousands of square kilometres (Ecos, 45, 
Spring 1985). It also seems probable that ground 
burners or ground release of ice nucleii could have a 
similar effect. On the ground, silver iodide is absorbed 
into coal dust, and this is then burnt when clouds form 
on hill crests. Strategic downwind hills can generate 
clouds and rain over large areas of land. 

Once initiated, however, such effects cannot quickly 
be stopped, and even in places like India or Ethiopia 
may create a little too much rain if ground storage 
systems are not previously developed to cope with the 
extra water. In arid or semi-arid areas, flood retardation 
basins, oversized swales, large sand dams, water 

TABLE 7.2 


Freshwater is only 3% ot all water on earth, and very little is in 
circulation, most beino locked up in storages. 



Ice and glaciers* 


Groundwater more than 

800 m deep 


Groudwater less than 

800 m deep 






Atmosphere (in circulation 
at any one time) 




'Frozen ground or permafrost is not assessed in this 
table. It represents a considerable storage (about 40% 

of the landmasses of Canada and the Soviet Union. 

spreading systems, pelleted seed of fast-growing 
plants, and in fact any sensible civil strategy to preserve 
soil and people from any effect of increased 
precipitation is a necessary prelude to cloud-seeding. 

Initial precipitation (due to increased bacterial or ice 
nucleii stimulus) increases can be as much as 30%, and 
subsequently averaged in Australia at 19% (17% in 
Israel) over weeks, falling to 8% in months. The 
cloud-seeding system promises to help increase 
monsoon or frontal rains in areas where suitable clouds 
occur without sufficient precipitation. This system can 
be very cheap for large land areas. For more data or 
references, contact the Cloud Physics Laboratory, 

TABLE 7.1 

RENEWAL TIMES OF ALL WATER IN BASIC STORAGES (seawater and freshwater)[From Southwick. C.H.. Ecology and the 
Quality ot our Environment. Van Nostrand Reinhold. NY. 1976.) 





(% of total water) 

(Turnover rates, cycles) 



37,000 years 

Glaciers and permanent snow 


16,000 years 

Groundwater (to 5 km depth) 


4,600 years 

(Actively exchanged) 


300 years 



13 years 



9 days 



13 days 

Biological water 


3.4 days 


Division of Atmospheric Research, CSIRO, Canberra, 

As similar effects (thunderstorms, rain) have been 
noted for tea leaf dust downwind of Kenya plantations, 
more homely strategies may also be developed if the 
underlying nucleation causes can be established. It may 
even be that the fires and dances of the old "rain 
makers" on a high hill were, in truth, effective. 
Certainly, fires of specific vegetation and dances with 
the right dust plume could help seed ice nucleii in 
clouds; quite local rain falls near some factory smoke 

Windward slope forests, cross-wind tree lines, and 
even slight earth rises of a modest 4-6 m have been 
observed to induce air humidity, cloud formation, and 
even rain, by orographic (uplift) effects on 
windstreams. Thus, we are not powerless in the matter 
of increasing local moisture by a series of sensible 
ground strategies based on providing trees, mounds, 
and cloud ice nucleii, and perhaps a serious attempt to 
induce these changes will in the near future bring relief 
to areas such as the Indian Deccan, the Sahel, and large 
areas of Australia and the USA subject to rainless cloud 

Strategically-selected cross-wind ridges of even 

modest height [3-20 m (10-65 feet)] are ideal sites for 
the planting of known tree "condensers" and 
cross-wind tree-lines. These ridges are most useful 
when lying in the path of the summer afternoon sea 
breezes that flow inland, or located where the air drifts 
in at night, such as on the Californian and sub-tropical 
trade-wind coasts. The clearing of trees from such sites 
may well induce long-term drought and create a 
drying effect for hundreds of kilometres inland. 

It is long past time that we also assessed vegetation 
for some of the following effects: 

• Ability to provide rain nucleii, as bacteria and 
natural sulphur particles, and also to effectively 
condense water from air at night. 

• The rainfftl.1 gffgd.s_lrQ. m forested rid ges , where 
forests exceed 6-10 m (19-32 feet) in height, on rainfall 
induced by streamline compression effects. This effect is 
credited with up to 40% of rainfall where now assessed 
in Sweden and Australia (Tasmania and Victoria). 

• IhgjQta 1.gffgg.t. of fo re s te d ca tchment area. 
Historical and recent evidence suggests that rainfall, 
streamflow, and cloud may all be seriously depleted by 
upland deforestation. Such effects are never assessed or 
costed against deforestation or wood-chipping. The 
soil erosion and salted land effects are, however, well 
known in deforested areas. 

Any conservationist policies of future effective and 
informed regional governments would first research 









Omits most of the biological effects but gives the broad schematic of 
the water cycle We can affect all parts of this cycle in adverse or 
beneficial ways. 


such effects, then quickly establish national forest and 
watershed management or restoration policies based on 
such research. For ourselves, as designers, the proper 
approach to land planning infers that we recommend 
permanent forests and the preservation of older forests 
on cross-wind ridges, and on steep (18° slope or more) 
sea-facing slopes. The preservation of alpine or upland 
absorption areas is also essential. 


Soil conditioning or “ripping" (see Chapter 8), 
providing it is followed by tree plantation, trace 
element additions, and a non-destructive agriculture of 
well-managed natural yields, sparse grazing, and 
conservation farming certainly increases (by factors of 
up to 70-85%) the ability of soils to hold and infiltrate 
water. Areas of up to 85% run-off can be converted to 
zero overland flow by a combination of soil condition¬ 
ing, swales, and water spreading to forests. 

As soils can contain many times the water of open 
storages or streams, then both the throughflow, 
baseflow, and water available for plants also increases. 
It follows that the CYCLING of water via 
evapotranspiration and rainfall also increases. Soil 
treatments now need to precede tree planting over 
almost every area that has been used by contemporary 
agriculture. In particular the barren areas used for 
constant cropping in dryland areas need soil treatment 
to initiate water absorption. Trees are essential to 
prevent water-logging of soils and soil salting in the 
long term. 

Cheap broadscale earthwork systems, and many minor 
forms of earthworks can aid the infiltration of overland 
water flow. PITTING, SWALES and WATER 
SPREADING are the main aids to getting fresh water to 
deeper storages for long-term use, and also to increase 
base flow. Diversion of surface flow to sand basins, 
dune fields, swamps, and soakage beds in 
earth-bermed fields all ensure resident water reserves 
for crop and trees, and longer-term storages for use in 
dry seasons. 

Diversion drains and their associated valves, slides, 
cross-walls, intakes, and irrigation systems enable 
effective water harvesting, dependable storage, and fast 
emergency use in normal rolling lowlands, hill country, 
and drylands. They can also recharge sand basins and 
swales from otherwise wasted overland flow, and 
damp our wildfires. 

Wherever precipitation exceeds the demands of 
transpiration and evaporation, small dams, wetlands, 
and swamps can proliferate. All of these act as long¬ 
term water and wildlife reserves in the total landscape, 
and many Australian farms are now drought-proof' 

due to sensible investment in Keyline or similar water 
conservation systems by the owners. Excellent technical 
manuals exist (see references at the end of this chapter). 

Dams and ponds are potential aquaculture sites, and 
the production of a diverse plant and fish or waterfowl 
protein product should also be considered during their 
construction. In humid areas, therefore, these water 
storages can occupy up to 20% of the landscape with 
great benefit in providing fish and a great variety of 
aquatic product, while at the same time moderating the 
effects of drought and flood. 


The great forests and the biological water storages in 
the form of fruits and nuts (such as the coconut) are the 
basis for the proliferation of life forms where no "free" 
water otherwise exists. In particular, browsers, insects 
and fungi draw on these biological tree reserves 
year-round, and perform a host of useful functions in 
any ecosystem. On atolls and arid islands of free- 
draining sands, the biological reserves are the main 
water reserves. This is often overlooked, except by 
those inhabitants dependent on the waters contained in 
fruits or nuts. Many plants such as cactus, palms, and 
agaves have specific tissues or organs to store water. 

In the local microclimate, the water in vegetation 
greatly moderates heat and cold excesses, and both 
releases to, and absorbs water from passing air streams. 
Essential crops such as cassava will produce crop as a 
result of the humidity provided by surrounding 
vegetation, so that even this side effect of vegetation is 
of productive use (New Scientist 29 May 86). 


Water can be captured off roof areas, roads, and other 
paved areas, and used for both drinking water and 
shower or garden water, providing it can be stored. 
Roof water is least polluted, or most easily treated for 
drinking and cooking in houses, while absorption beds 
are sufficient for the muddy or polluted run-off from 
roads and parking areas. 

_ 73 _ 


For the serious small dam and earth tank builder, there 
is no substitute for such comprehensive texts as that 
recently compiled by Kenneth D. Nelson (1985). This 
small classic deals with catchment treatments, run-off 
calculations, soils, construction, outlets, volume and 
cost estimates, and includes detailed drawings for most 
adjunct structures. 

However, like most engineers. Nelson concentrates 
mostly on valley dams (barrier or embankment dams), 
and less on the placement of dams in the total designed 


landscape. Few dam builders consider (he biological 
uses of dams, and the necessary modifications (hat 
create biological productivity in water systems. 

A second essential book for water planning in 
landscape is P. A. Yeomans' Water for Every Farm/The 
Keyline Plan (1981 ) s . This very important book, written 
in 1954, is without doubt the pioneering modern text on 
landscape design for water conservation and 
gravity-fed flow irrigation. As it also involves 
patterning, tree planting, soil treatment, and fencing 
alignment, it is the first book on functional landscape 
design in modern times. 

There are two basic strategies of water conservation 
in run-off areas: the diversion of surface water to 
impoundments (dams, tanks) for later use, and the 
storage of water in soils. Both result in a recharge of 
groundwater. As with all technologies, earthworks have 

quite specifically appropriate and inappropriate uses. 
Some of the main productive earthwork features we 
create are as follows: 

• Dams and tanks (storages); 

• Swales (absorption beds); 

• Diversion systems or channels; and 

• Irrigation layouts, and in particular those for flood 
or sheet irrigation. 


Small dams and earth tanks have two primary uses. 
The minor use is to provide watering points for 
rangelands, wildlife, and domestic stock; such tanks or 
waterholes can therefore be modest systems, widely 
dispersed and static. The second and major use is to 
contain or store surplus run-off water for use over dry 


periods for domestic use or irrigation. The latter 
storages, therefore, need to be carefully designed with 
respect to such factors as safety, water harvesting, total 
landscape layout, outlet systems, draw-down, and 
placement relative to the usage area (preferably 
providing gravity flow). 

A separate category of water storages, akin to fields 
for crop or browse production, are those ponds or wet 
terraces created specifically for water crop (vegetation or 
mixed polycultural systems of aquatic animal species). 

Open-water (free water surface area) storages are 
most appropriate in humid climates, where the potential 
for evaporation is exceeded by average annual rainfall. 
There is a very real danger that similar storages created 
in arid to subhumid areas will have adverse effects, as 
evaporation from open water storages inevitably 
concentrates dissolved salts. Firstly, such salty water 
can affect animal health. Secondly, the inevitable 
seepage from earth dams can and does create areas of 
salted or collapsed soils downhill from such storages. 
And in the case of large barrier dams, so little water 
may be allowed to bypass them in flood time that 
agricultural soils, productive lakes, and estuaries may 
lose more productive capacity by deprivation of 
flush-water and silt deposits than can be made up (at 
greater cost) by irrigation derived from such lakes. 

Dryland storage strategies are discussed in Chapter 
11. What 1 have to say here is specifically addressed to 
humid areas and small dams unless otherwise noted. 

Earth dams or weirs where retaining walls are 6 m 
(14 feet) high or less, and which have a large or 
over-sized stable spillway, are no threat to life or 
property if well-made. They need not displace 
populations, stop flow in streams, create health 
problems, fill with silt, or block fish migrations. In fact, 
dams or storages made anywhere but as barriers on 
streams effectively add to stream flow in the long term. 

Low barrier dams of 1-4 m (3-13 feet) high can assist 
stream oxygenation, provide permanent pools, be 
"stepped" to allow fish ladders or bypasses, and also 
provide local sites for modest power generation. While 
almost all modern assessments would condemn or ban 
large-scale dams (and large-scale power schemes) on 
the record of past and continuing fiascos, a sober 
assessment of small water storages shows multiple 

Given the range of excellent texts on small dams 
(often available from local water authorities, and by 
mail order from good bookstores), 1 have therefore 
avoided specific and well-published construction 
details, and have here elaborated more on the types, 
placement, links to and from, and function of small 
dams in the total landscape. Yeomans ( pers. comm., 
1978) has stated that he believes that if from 10-15% of 
a normal, humid, lowland or foothill landscape were 
fitted with small earth storages, floods and drought or 
fire threat could be eliminated. 

Not all landscapes can cost-effectively store this 

P-AJT c* r /wrtiK7r.Ni 

OWt/g* WT' CobjZAV^ 5K>FE5 


Schematic ol water storages with respect to slope, forests, and 


proportion of free surface water; some because of 
free-draining soils or deep or coarse sands. Other areas 
are too rocky, or of fissured limestone, and yet others 
are too steep or unstable. But a great many productive 
areas of clay-fraction subsoils <40% or more clay 
fraction) will hold water behind earth dams, below 
grade levels as earth tanks, or perched above grade as 
"turkey's nest" or ring dams. There are very few 
landscapes, however, that will not store more soil water 
if humus, soil treatment, or swales are tried; the soil 
itself is our largest water storage system in landscape if 
we allow it to absorb. 

Almost every type of dam is cost-effective if it is 
located to pen water in an area of 5% or less slope. 
However, many essential dams, if well-made and 
durable, can be built at higher slopes or grades, made 
of concrete, rock-walled, or excavated if water for a 
house or small settlement is the limiting factor. Each 
and every dam needs careful soil and level surveys and 
planning for local construction methods. 


There are at least these common dam sites in every 

extensive landscape: 

SADDLE DAMS are usually the highest available 
storages, on saddles or hollows in the skyline profile of 
hills. Saddle dams can be fully excavated below ground 
(grade) or walled on either side of, or both sides of, the 
saddle. They can be circular, oblong, or "shark egg” 
shaped with horns or extensions at either end (Figure 

Uses : wildlife, stock, high storage. 

R1DGEPOINT DAMS or "horseshoe” dams are built 
on the sub-plateaus of flattened ridges, usually on a 
descending ridgeline, and below saddle dams. The 

shape is typically that of a horse's hoof. It can be made 
below grade, or walled by earth banks (Figure 7.5). 
Uses : As for saddle dams. Only of limited irrigation 
use, but very useful for run-off and pumped storages. 
Note that both saddle and ridge dams can act as 
storages for pumped water used for energy generation. 

KEYPOINT DAMS are located in the valleys of 
secondary streams, humid landscapes, at the highest 
practical construction point in the hill profile, usually 
where the stream profile changes from convex to 
concave; this place can be judged by eye, and a 
descending contour will then pick up all other 
keypoints on the main valley (Figure 7.6). 

Uses : Primarily to store irrigation water. Note that a 
second or third series can be run below this primary 
series of dams, and that the spillway of the last dam in 
a series can be returned "upstream" to meet the main 
valley, effectively spilling surplus to streams. 

CONTOUR DAM walls can be built on contour 
wherever the slope is 8% or less, or sufficiently flat. 
Contours (and dam walls) can be concave or convex to 
the fall line across the slope (Figure 7.7). 

Uses : Irrigation, aquaculture, or flood-flow basins in 




£**e 'XXT*>H aa 


A II used in senes, no spillway is built and the overllow goes to the 
next dam. and eventually to a stream. Fitted lor irrigation on lower 

B The keyline (heavy dashes) links keypoints in primary valleys 

semi-arid areas. 

BARRIER DAMS are always constructed across a 
flowing or intermittent stream bed. These dams 
therefore need ample spillways, careful construction, 
fish ladders on biologically important streams, and are 
made most frequently as energy systems, but are also 
used for irrigation if they are constructed well above 
the main valley floors where crops are grown (Figure 

TURKEY S NEST DAMS or above-grade tanks; water 
has to be pumped in to these, often by windmill or solar 
pump. They are common in flatlands as stock water 
tanks or for low-head irrigation (Figure 7.9). 

CHECK DAMS. There are many forms of barrier 
dams not intended to create water storages, but to 


The engineer's dam ' Can affect fish, migration, and be difficult to 
spill; works well as part of a keyline senes only 


regulate or direct stream flow. Even a 1-3 m (3-10 foot) 

an hvT* 5 , 3 S ' ream head to d“ve 
stream Z JV am ' '° fl ' 3 wa,erwh eel. to divert the 

rr i % rrssx ^ Te - k 


S,I ‘ afi0n (Fi 8 ure 7 -I»-13). P he 

reckoned mesh S: h ,n . dry,ands ' P ermeab Ie barriers of 
. aSke,S ( S abion *> will create silt 
and water-spreading across eroding valleys. The 

5' Mt; OW C«OVMt> 

C<T.RC„u**_ lhJ PLA,^ 



walbo bu ‘ ,0r ,arm constnJ ction, 

712 the ou^: 5 ,W,) hi8h are Usual ' A. with Figure 

.h^ g ” n com^rrj“ a **» 

and revitalise,ion rones. (FigumtlT ^ US38e ' 



(ractmns); *** ° U ' 3 “"I* P“ *" Pressing day 

• Grade behind wall (lower slopes give greatest 



Ptvee<*oN prajvj 

Ofhe&L OROAy 


FIGURE 7.10 

Diverts intermittent flow to ridges. storages. or canals on contour. 


PA-5C HPr 

«STRg*M r*C*l L ( 

FIGURE 7.11 


'° MSS - *»*■ a "» Prevents raps, iiood 

FIGURE 7.13 


^ViSSft 3 “""" ™*>' p«w 


T&+tsJB4i<£ <zeCTTc^ 

. v.vv/l 


Lvv- > :• v .• * 


UNIT . n GH5to N " 



6A&osi ^Ou>\/Auey 


FIGURE 7.14 

SffiMSKS" 0 wi " ta *“ - 

capacity); feet), not counting the holes behind such walls caused 

• Downstream safety of structures and houses (a key by their excavation. Therefore we speak of depths of 

factor in large dams); 4.5-6 m (15-20 feet) for small earth dams. Few of us will 

• Height above use points (gravity flow is desirable); want to build farm dams higher, and we must get good 

and advice if we wish to do so. 

• Available catchment or diversion. Slopes to crest should be concave, and every 25 cm 

Tamped earth with some clay fractions of better than (10 inches) a machine such as a roller, or the bulldozer 

50% is a waterproof barrier up to heights of 3.6 m (12 tracks themselves, should ride along and tamp down 

FIGURE 7.16.A 

P. A. Yeomans' 'Keytme* system provides drought-proolmg tor farms in English on total water design tor foothill farms, access, tree belts, 
with very low maintenance and operating costs; his was the first book soil creation, low tillage, and creative water storage 






1't iz 

bS 12. 

+ o 
tb 3 US 
1 - 2 - 







5 s-i 














V\ v 




'•O lo* 






FIGURE 7.16.B 


P A Yeomans' former properly 'Yobarme*. after 17 years of keyfme 
irngalion development, covering about 307 ha (758a ). The road on 

the southern edge of Yobamie is located along a mam ridge. Note the 
primary valleys and primary ridges falling to Redbank Creek to the 
North For further information and photographs see Yeomans*) 


the earth. This, like the exclusion of boulders and logs, 
grass clumps and topsoil, is critical to earth stability 
(shrinkage of well-compacted dams is less than 1 %). 
Earth so rolled should be neither so dry as to crumble 
nor so wet as to slump or squash out under the roller. 

A key should be cut to prevent shear and cut off any 
base seepage. This is needed on all walls 1.8 m <6 feet) 
or more high, otherwise the base should be on a 
shallow- clay-filled ditch. Slopes are safe at a ratio of 3:1 
(inner) and 2 or 2.5:1 (outer), freeboard at 0.9 m (3 feet), 
key at 0.6-0.9 m (2-3 feet) deep. In suspect soils, the 
whole core can be of carted clay (Figure 7.17). 

The wall can curve (out or in), but if carefully made 
as diagrammed and provided with a broad spillway, 
should be stable and safe forever, barring explosions or 
severe earthquakes. 

The SPILLWAY base should be carefully surveyed at 
1 m below crest and away from the wall or fill itself 
(don't try to judge this, measure it), and a SIPHON or 

BASE OUTLET pipe fitted with baffle plates placed to 
draw off water (Figure 7.18). 

The efficiency in capacity of dams depends on the 
flatness of the area behind the wall. A "V" valley or "U” 
valley, plateau, or field should be as level as can be 
chosen for greatest efficiency. The key to efficiency is 
the length of the dam wall, compared with the ' length" 
of water dammed. If the back-up is greater than wall 
length, then this is a measure of increasing efficiency of 
energy used or earth moved for water obtained. A 
careful survey of grade plus dam length gives this data 
before starting the wall. Some dam sites are very 
cost-effective, especially those short dams at 
constricted sites where the valley behind them is 

Small dams of this nature are a jewel in the 
landscape. Fenced and planted to 30-60 m of forest and 
fruit surround, they will provide biologicially clean, if 
sometimes muddy, water, and if the topsoil is returned. 


lime used, and edges planted, mud will decrease and 
eventually clear. For water cleanliness and parasite 
control, cattle, sheep, and other animals should be 
watered at spigots or troughs, not directly at the dam. 
Troughs are easily treated with a few crystals of copper 
sulphate to kill snails and parasitic hosts; dams stocked 
with fish will do the same job. 

Crests can be gravelled and safely used as roads to 
cross valleys or bogs, and special deep areas, islands, 
peninsulas, and shelves or benches made inside the 
dam for birds, plants, and wild-fire-immune houses. 


There are several ways to seal leaking dams: 

• Gley; 

• Bentonite; 

• Explosives; 

• Clay; and 

• Impermeable membranes. 

GLEY is a layer of mashed, wet, green, sappy plant 
material sealed off from air. Although the very green 
manure of cattle is preferred, shredded, sappy 
vegetation will also work. It is carefully laid as a 
continuous 15-23 cm (6-9 inch) layer over the base and 
gently sloping sides (ratio of 1:4) of a pond, and is 

covered completely with earth, cardboard, thick wet 
paper, plastic sheets, or rolled clay, and allowed to 
ferment anaerobically. This produces a bacterial slime 
which permanently seals soil, sand, or small gravels. 
Once ferment occurs, the pond is pumped or hosed full 
of water, and the paper or plastic can be later removed. 

I have used carpets and odd pieces of plastic sheets 
overlapped with good results. In cold areas, ferment 
can take a week or two, in tropics a day or so. Lawn or 
second-cut grasses, papaya and banana leaves, 
vegetable tops or green manure all serve as the base 
layer. I believe that in very good soils, especially in the 
tropics, it may be possible to grow the gley as a mass of 
Dolichos bean and just roll it flat before sealing it (Figure 

Modifications are: 

• To pen and feed a herd of cattle in the dry dam 
until the bottom is a manurial pug; occasional watering 
assists this process. 

• To strew bales of green hay and manure on ponds 
that leak slightly, producing algae which seal minor 

• To sow down green crop in the dry dam, spray 
irrigate and feed it off regularly with cattle. 

BENTONITE is a slippery clay-powder derived from 
volcanic ash. It swells when watered and will seal 

fEjrpcncN vavc acttcn 


Sown wrTW CKA9.CS 



' ScoCK- / 


0-3** Ci*rt (Key'* 

-tAlP ON) _ &ACCU& V 

Soutp HATeRfM, VuATfrS 
c vQ. Cuu. cewi'.rw 

FIGURE 7.18 

DAM WITH LOCK PIPES. be fitted with a base pipe. Smaller dams use siphon over the dam wall 

A large earth dam feeding irrigation canals in the Keyline system can to gardens and houses. 

WMWL PU*Pei> I* APT&*. 

■6-^cm of -tsrry 


U&A oF t**! 

FIGURE 7.19 

With great care taken to slope side and place ferment material, this 

-SIPC- 5LoftW* 

3 oft -f 1 I To 

technique will seal ponds in sands, gravels, shales, or leaking 


clay-loams if rototilled in at 5-7 cm (2-3 inches) deep 
and rolled down. However, it is expensive and doesn’t 
always work. Cement and tamping plus sprinkling 
might be preferable, or a bituminous spray can be 
rolled in after tilling. In clay soils, salt or sodium 
carbonate can have the same effect. 

EXPLOSIVES are sometimes used to compact the 
sides of full dams, and consists of throwing in a 3-5 
stick charge of dynamite. This works well at times, but 
is dangerous if you own a retriever, or if the dam wall is 
poorly compacted to start with. 

CLAY is expensive if it has to be carted in, but it is 
often used to seal dams near a clay pocket. The clay is 
spread and rolled 23-30 cm (9-12 inches) thick over 
suspect areas. 

IMPERMEABLE MEMBRANES can be of w-elded 
plastic, neoprene, or even poured concrete. Imperme¬ 
able membranes are too expensive to use on any but 
critical dams, which may mean a guaranteed water 
supply to a house or garden in very porous areas. Using 
membranes enables banks to be steeper than in any 
other earth-compaction or gley system, so that more 
water can be fitted into smaller space. It is not 
"biological" unless a sand or topsoil floor is also added 
over the sealing layer, when fish or plants can be 

Earth storage is now- the cheapest, easiest, and most 
locally self-reliant method of water conservation. 
Unless both cities and farms use such methods, clean 
water will deservedly become known as the world’s 
rarest mineral, ill-health will be perpetuated, and 
droughts and floods alike become commonplace. None 
of these are necessary. 

Costs vary greatly; as a rough guide, water stored in 
soil and humus is the cheapest and of greatest volume, 
surface dams next cheapest, and tanks dear, but still 
much less expensive than piped water from mains 
supply. I can only urge all people of goodwill to 
promote, fund, and investigate water and w-ater 
storage, water energy and water cleanliness, as the 
chlorinated, metallic, asbestos-fibred, poisonous water 

of modern centralised systems is producing such 
epidemic disease and illness as cancer, bone marrow 
failure, and gastrointestinal disorder. 

If a 22,500 1 tank costs 20 units of money, the same 
units in a sensible eath storage pays for 2,500,00 1, or 
about 100 times as much water. Up to 135,000-2,500,000 
I tanks get cheaper, as less concrete is used for more 
w-ater. That is, a large tank is relatively cheaper than a 
small tank. Above 22,500 1, such tanks are usually 
poured on site; below this, they are carted from a 
central manufacturing site. 

Dams, in contrast, begin to cost more as the height of 
the wall rises. About 3 m (10 feet) of retaining wall is 
the limit of cheap dams. Above this, costs rise rapidly 
as greater skills, more expensive and massive materials, 
more complex controls of levels, and much greater 
environmental risks take their toll. 

As noted, “cheap" water in dams depends on the 
choice of site, so that very low dams on well-selected 
sites impound 20-100 times more water than the same 
earth used on steeper sites, where every unit of earth 
moved equals a unit of water. However, even earth 
tanks excavated below grade are at one-tenth the price 
of concrete tanks above grade. 

Where are tanks, modest dams, and massive dams 
appropriate? Tanks are appropriate on isolated 
dwellings, in flatlands, and everywhere in cities and 
urbanised areas. Dams of from 22,500 to 4.5 Ml are best 
built on any good site in country and parkland areas. 
Massive dams are appropriate hardly anywhere but the 
the rock-bermed or glaciated uplands of solid and 
forested hills, subject to low earthquake risk and then 
only for modest domestic (not dirty industrial) power 


Cultural and historical precedent may determine how 
earth is moved and used, or even if it can be moved at 
all. Thus, an Australian, accustomed to a great variety 
of surface storage, is astounded that there are no 



Storage tanks cost about 100 times the cost ol dams tor the same 
amount ot water stored: cost-size schematics tor both are given 


significant domestic rainwater tanks in Europe, the 
USA, or India (where clean drinking water is rare), that 
British, American, and Brazilian farmers rarely use 
multiple earth storages of water, and that expensive 
pipelines and bores are the preferred 'alternative", even 
where local rainfall often exceeds local needs. 

The simple forms for making concrete tanks cost a 
few hundred dollars, and may be used hundreds of 
times. About 22,500 1 provides a family with all needed 
water (drinking, showers, cooking, modest garden 
water on trickle) for a year; tank water is renewed by 
rain at any time of year. Every roof, whether domestic 
or industrial, would fill many such tanks, and simple 
calculations (roof area x average rainfall in millimetres 
or inches) and conversion to litres or gallons gives the 
expected yield. 

Granted that roof areas themselves can be 
contaminated by birds, dust, or industry, the first 
precaution is to reject the first flow-off of water, and 
use it on gardens or in swales. Two methods for doing 
this are shown in Figure 7.21. 

As for the entry of insects, birds, or rodents to tanks 
(and this includes mosquitoes), a "U" pipe entry and 
exit, a sealed tank roof, and an overflow pipe emptying 
to a gravel-filled swale all effectively exclude these 
potential nuisances. If birds persistently perch on roof 

ridges, a few very fine wires or thread stretched along 
the ridge as a 10 cm (4 inch) high "fence" will 
discourage them. 

Gutters on roofing can be cleaned out regularly, or 
"leaf-free” gutters or downpipes fitted (about 3 or 4 
types are commercially manufactured; some systems 
are illustrated in Figure 7.22). 

Given that most dust and leaves are removed, 
residual organics are usually harmless. These "fix" as an 
active biological velvety film on tank walls and bases. 
Taps or outlet pipes are normally fitted 15-20 cm (6-8 
inches) above any tank floor to allow such a film to 

Finally, a net or bag of limestone, shell, or marble 
chips is suspended in the tank. This creates hard 
(alkaline) water, preventing heavy metal uptake from 
the water and decreasing the incidence of heart attacks 
in those using the tank. Washing and shower water can 
be soft (acid) but the water we drink is best made 
alkaline for the sake of health. 

It makes far more sense to legislate for such tanks on 
every roof than to bring exotic water for miles to towns; 
it will also ensure that clean air regulations are better 
observed locally, that every house has a strategic water 
reserve, and that householders are conservative in their 
use of water. 

Steep H«ce-r. 

v EMny frAxe-T ft*. 


/eve*y wo*.. 

'(At* se H>yrSex> 

&y A.5HACC- TAP). 

' Co*. 


FIGURE 7.21 


The first rams wash the roof, and are rejected: these systems 
automatically reset when empty 


IGURE 7.22 
Self-cleaning and leaf-free gutters or downpipes are useful where 
trees overhang a house; cone to pipe is also useful to collect water 
from rock domes 


Swales are long, level excavations, which can vary 
greatly in width and treatment from small ridges in 
gardens, rock-piles across slope, or deliberately- 
excavated hollows in flatlands and low-slope 
landscapes (Figure 7.23). 

Like soil conditioning or soil loosening systems, 
swales are intended to store water in the underlying 
soils or sediments. They are, simply, cross-flow dry 
channels or basins intended to totally intercept 
overland flow, to hold it for a few hours or days, and to 
let it infiltrate as GROUNDWATER RECHARGE into 
soils and tree root systems. Trees are the essential 
components of swale planting systems, or we risk soil 
waterlogging and a subsequent local rainfall deficit 
caused by lack of evapotranspiration of the stored 
water. Thus, tree planting must accompany swaling in 
arid areas. 

Swales should ideally not exceed in width the total 
crown spread of the fringing trees planted to use the 
stored water absorbed into the swale sediments. Trees 
overshadc and cool the soils of swales, further reducing 
the risk of evaporation and dissolved salt concnetra- 
tion, or water loss. Although swales can also be grazed, 
few grasses can effectively remove the absorbed water 
to re-humidify airstreams. 

Swales are therefore widely used in arid to sub- 
humid, even humid areas, on both fairly steep slopes 
and flatlands, and in both urban and rural areas. They 
are appropriate to road and other silty or contaminated 
run-off harvest (where the dust or tar oils washed off 

have no adverse effect on tree growth). 

The essentials of swale construction are simple: they 
are all built on contour or dead level survey lines, and 
are neither intended nor permitted for water flow. Their 
function is just to hold water. Unlike dams, swale banks 
and bases are never compacted or sealed (although 
small tanks can be sunk in swale bases for watering 
livestock or trees). Conversely, the swale soils can be 
gravelled, ripped, or loosened to assist water 
infiltration. The swale depth and width can be varied to 
cope with the speed of infiltration locally, so that wider 
and shallower swales are made in sands, narrower and 
deeper swales in clay-fraction soils. 

After an initial series of rains that soak in a metre or 
more of water, trees are seeded or planted on either 
bank or side slopes of the swales. This can take two wet 
periods. Thereafter, it takes about 3-5 years for tree 
belts to overshade the swale base, and to start humus 
accumulation from leaf tissue. (Humus will accumulate, 
however, by wash-down and wind movement from 
bare or uphill areas.) 

Early in the life of an unplanted swale, water 
absorption can be slow, but the efficiency of absorption 
increases with age due to tree root and humus effects. 
As this happens, it is possible to admit water to swales 
from other areas, leading it in via DIVERSION DRAINS 
DRAINS. This "exotic" water from unused road or rock 
surfaces or overland flow can enable the planting of 
high-value trees of higher water demand or a new set 
of swales to be constructed. 

Every sub-humid and arid townscape can, with great 
energy gain and much reduced cost for roading and 
water use, fit all roads and paved areas with swales, 
along which tree lines shade pavement and reduce heat 
oases while they produce fuel, mulch, and food 
products. Every roof tank overflow, and some 
greywater wastes can be led to swales (if boron 
detergents are not used). 

Swales interpenetrating the suburban development of 
Village Homes in Davis, California (Michael Corbett, 
designer) accept all road and excess roof run-off, and 

FIGURE 7.23 

Swales on contour do not (low. they first stop and then infiltrate 
overland How. Swales on hillsides are part ol access or production 


support hundreds of productive trees in settlement. 
Water penetrated soils to 6 m (19 feet) deep after a few 
years of operation, and swales were self-shaded after 
3-4 years of tree growth. In Hawaii and in central 
Australia, swales I have designed produced fast growth 
in trees in volcanic cinder and sandy soils. 

Swales in Australian drylands have consistently 
grown larger and healthier water run-off fed trees than 
have open plantings. In arid areas, it is imperative to 
plant trees on swales, or we risk salt concentration and 
soil collapse downhill. All swales are therefore 
temporary events, as trees supplant their function; they 
are precursors to rehabilitation of normal forests in their 
region. Natural swales in humid forests (Tasmania) not 
only generate much larger trees and provide level 
access ways, but support a thick humus and specialised 
plants on the swale floors. Orchids, fungi, and ginseng 
do better in swales. 

Most swales should be adjusted (by widening, 
gravelling, or ripping) to absorb or infiltrate all water 
caught in from 3 hours to 3 days. Fast absorption will 
not harm most tree species, although trees such as 
chestnuts and citrus may need to be planted on nearby 
spoil banks for adequate root drainage. I believe swales 
to be a valuable and greatly under-used earth form in 
most climates, including upland and plains areas of 
snow-drift in winter. 

In summary, a swale is a large hollow or broad drain 
intended to first pool, then absorb all surplus water 
flow. Thus, the base is ripped, gravelled, sanded, 
loosened, or dressed with gypsum to allow water 
INFILTRATION. Trees ideally overshade the swale. The 
base can be uneven, vary in width, and treated 
differently depending on the soil type. The spoil is 
normally mounded downhill or (in flat areas) spread. 
Water enters from roads, roof areas, tank overflows, 
greywater systems, or diversion drains. 

The distance between swales (the run-off or mulch- 
planted surface) can be from three to twenty times the 
average swale width (depending on rainfall). Given a 
useful swale base of 1-2 m (4-6 feet), the interswale 

space should be 3-18 m (12-60 feet). In the former case, 
rainfall would exceed 127 cm (50 inches), and in the 
latter it would be 25 cm (10 inches) or less. In humid 
areas, the interswale is fully planted with hardy or 
mulch-producing species. In very dry areas, it may be 
fairly bare and exist mainly to run water into swales. 

Mulch blows into, can be carried to, or is grown and 
mown in swales. Fine dust and silts build up in swale 
bases, and domestic wastes can be buried here as a 
mulch-pit for hungry plants. The swale and its 
spoil-bank make a very sheltered starting place for 
plants on windy sites, and the lower slope swales can 
be planted mainly to Casuarina or leguminous trees to 
prevent upslope winds. Ridges should always have 
windbreak and condensation plants of hardy and 
useful species ( Casuarina , Acacia, Leucaena, silky oak, 
pine, cypress). Windbreaks can occupy every sixth to 
tenth swale on sites where wind is a limiting factor. It is 
better to plant on the downslope side to allow mulch 
collection in the swale base for use elsewhere. 

Swale sections can be over-deepened, so that 
although the swale lip is surveyed level, its floor may 
rise and fall. Deepening is most effective in clay- 
fraction soils, and may result in shallow’ ponds for 
water-needy crop. Widening is most effective in sand 
or volcanic-fraction soils, and readily admits water to 
the ground table. 

Two other pit systems are useful in swales: one mulch 
and manure-filled for heavy nutrient feeders (yams, 
bananas, etc.) and the other to hold oil drums, plastic 
liners, or tyre ponds as a sealed water reserve for 
watering young plants. These can be planted with lotus, 
kangkong, watercress, Chinese water chestnut, or like 

Keeping the swale width to the tractor, donkey cart, 
foot track or wheelbarrow access width that one has 
planned, sections can be widened at regular intervals to 
take assemblies of plants, to dig ponds or mulch pits, 
and to plant trees of higher water need. This leaves 
access open and enables many assemblies, species, and 
constructs to be built along the swale as need dictates. 



FIGURE 7.24 


Manures Irom animals placed in swales, or canals feeding wet 
terraces, provide nutrients via water transport tor swale crops, and 
associated trees 

rc-n&£ Rcore- 




FIGURE 7,25 


Silt trom swales is graded out or shovelled up to tree lines on 

downslope side Swales can be widened over time to create a terrace 


Diversion drains are gently sloping drains used to lead 
water away from valleys and streams and into storages 
and irrigation systems, or into sand beds or swales for 
absorption. If low earth-walls are raised across the flow 
channels of larger diversion drains, these then act as a 
series of mini-swales for specific tree sites, while 
surplus water flows on to storages. Diversion drains 
differ from swales in that they are built to flow after rain 
(from overland flow or from feeder streams). They are 
the normal and essential connectors of dam series built 
on the Keyline systems, so that the overflow of one dam 
enters the feeder channel of the next. 

Such diversion systems need careful planning and 
survey, with drain bases sloping as little as 1:6000 in 
fine sands. Dam crests and irrigation drains need 
equally careful placement. Even without a stream 
intake, diversion drains will gather water from 
overland flow in as little as 1-1.5 cm (1/2 inch) of rain 
over 24 hours, so that isolated dams are normally fitted 
with diversion drains even in quite dry country. 
Diversion drains can be led to broad level swales in 
drylands, or made of simple concrete or stone walls 
across solid rock faces. In the Canary Islands, these 
gather rock run-off which is led to underground cave 
storages or large open tanks. Simple sliding gates across 
or in the downhill banks of such drains allow 
controlled flow, controlled irrigation, and (in floods) 
by-passing of dams. 

Spill gates can be FIXED (concrete slide holders and 
aprons) or MOVEABLE (plastic sheets weighted with a 
chain sewn into the foot, and supported across the 
drain by a light pipe sleeved into the top). These latter 
are called "flags' (Figure 7.27), 

Slide gates can open on to ridge lines, and water then 
spreads downhill, while plastic flags can be placed and 
taken up at any point along a drain. This enables one or 
two people to water 200-240 ha (400-600 acres) in a 
morning. It is also an effective wildfire control system 
in forested areas. For sophisticated wildfire or irrigation 
control, both slide gates and dam-base gate valves can 
be remotely operated, by radio signal and storage 
batteries or buried electrical conduits, to power small 
motors or hydraulic slides. A complete wildfire control 
can be achieved by dams and sheet irrigation, and 

using infrared sensers and automatic spill-gates. Such 
systems remove the risk for fire-fighters, and allow 
forests to regenerate in semi-arid areas. 

Interceptor drains . These drains-or rather, sealed 
interceptors—act in the opposite tense to diversion 
drains. These earthworks are specifically designed (by 
Harry Whittington of West Australia) to prevent 
overland waterflow and waterlogging, which has the 
effect of collapsing the dryland valley or downslope 
soils of a desert soil catena. Thus, they ideally totally 
intercept overland flow, and direct it to streams or 
valley run-offs. They can be cross-slope as are swales, 
but they differ from diversion drains and swales in that 
their construction always involves the ramming (by 
bulldozer blade) of subsoil layers hard against the 
downhill bank. This effectively prevents or impedes 
water seepage through the downhill wall of the 
interceptor bank. Moreover, they are always 1.5-2.5 m 
(5-8 ) deep, carefully spaced, and effectively stop not 
only overland flow but also salt water seepages in 
shallow sand seams. In effect, they isolate large blocks 
of soil from waterlogging and salt seepage. 

After this preparation, trees can be planted in 
previously desertified soils. 

Where deeper sand seams carrying salty water are 
located, these can be trenched out and stopped with a 
vertical plastic barrier, backed by compacted clay on the 
uphill side. 

Made to flow at 1:600 to 1:1500 cross-slope 
interceptors effectively cut up incipient or degraded 
croplands subject to desertification into blocks of 100 m 
(330 feet) to a maximum of 300 m (985 feet) wide, 
isolating each block from flooding and the salty 
"cascade" flow from uphill. Surplus water is carried off 
in streams. Interceptor banks also cut off seepage from 
salt lakes, and can divert early (salted) overland flow’ 
around saltpans, letting later fresh flood water fill the 
pans or shallow lakes. 

Sp reader drain s or banks are intended to spill a thin 
sheet of surplus (overflow) water dow-n a broad grassy 
slope, either for irrigation or (in deserts) to prevent 
channel scour and gullying. They are normally made to 

FIGURE 7.27 

A plastic sheet, one end supported by the channel banks, the other 
wighted by a chain, lorms a temporary dam. causing the channel to 
flood out and irngate land downhill. 


take any overflow from swales and dams, and may be 
tens or hundreds of metres long. Spreader banks have 
the lower side dead level, and compacted or even 
concreted. Water enters from a dam, swale, or minor 
stream and leaves as a thin sheet flow downslope. Spoil 
is piled uphill, preferably in mounds, or removed to 
allow downhill sheet flow to enter the spreader ditch 
(Figure 7.28). 

For irrigation areas of flatlands, the bank is often 
pierced by a series of dead-level pipe outlets, each 
feeding an irrigation bay (itself planed flat), to which 
water is confined by low side walls (STEERING 
BANKS). At the lower end of that bay, a TAIL 
DRAIN—a surplus water drain—leads off excess water 
to a stream or secondary storage dam. In such cases, the 
uphill or primary feeder drain is called the HEAD 
RACE, and has cross-slides that block flow; this causes 
the levelled pipes to flood out into the bays. Sometimes 
the pipes are replaced with level concrete sills and in 
old-established spreader banks, the whole of the lower 
lip may be concreted to give a permanent level spill 

immune to breakage by cattle or vehicles. 

Spoil lines uphill from spreader banks are best piled 
or at least broken bv frequent openings to allow 
downhill overland flow to enter the drain without 
carrying silt loads. 

In any landscape, a subtle and well-planned 
combination of dams, drains, spreader banks, swales, 
and appropriate pipes, gate-valves, spill gates, flags, or 
culverts will harvest, store, and use surplus flood or 
overland flow waters. These are used to flush out salts 
from soils, spread water evenly over crop, put out 
wildfires, and modestly irrigate land. It is a matter of 
first deciding on, then surveying any or all these 
systems, and above all of considering the long-term 
effects on the immediate landscape and the soils. 

Ml earthworks can be regarded as REHABILITIVE 
and remedial if they replace salted and eroded lands 
with perennial browse or forests. They can be seen as 
DAMAGING and exploitative if used to irrigate high 
water-demand crop (like luceme/alfalfa) in drylands, 
to cut off flow to dry areas, or to run water for 
unessential uses to large urban centres devoted to 
lawns and car washes. 

_ 7A _ 


In cities, water is chlorinated and fed back into the 
system, sometimes mixed with seawater or 'treated’' 
waste water to give it that city taste so typical of, e.g. 
Las Palmas in the Canary Islands. Surplus sewage. 


& f l: * D Q FALL tgE 4j£ 

FIGURE 7.29 


layout for channel irrigation; bays should not exceed 100 m long or 

water can be wasted to evaporation. See also Figure 7.30. 

M7Vf Bean rtp oBV 

frjNP flP TgtffcACE- 
CfcR fRoPSy 


(*S V fcope rNTo 


with ouecftovJ—A pAt>r). 


untreated, is often passed to sea, with bacteria, viruses, 
and parasites intact for bathers to wallow in. 

All of this arises from the frequent, wasteful, and 
unnecessary flushing of toilets by those of us living in 
the effluent society. In Sweden, it is compulsory to use 
dry toilets in remote, unsewered, or unsuitable areas. In 
the USA, UK, and Australia, one has to fight hard to get 
permission to use these, as it is the vested interest of 
industry and town clerks to supply and charge for 
sewerage systems. 

However, no clean water need be used to flush toilets 
if there is a diversion from a hand-basin to the toilet 
tank. In Australia at least, hand-basins moulded in to 
toilet flush tanks are available (Figure 7.31). It is 
essential to use low-flush toilet bowls with such 
systems, as they otherwise flush incompletely, and 
build up heavy pathogenic bacteria populations. 

This is a simple solution to 40% of domestic water 
misuse, and encourages hand cleanliness rather than 
the false cleanliness/tidiness of toilet flushing for its 
own sake. 

Dry toilets are not always appropriate, except in cities 
and other water-critical areas. They are unnecessary 
on farms or in well-drained soils, or wherever sewage 
is used to produce methane by anaerobic digestion in 

tanks. In fact, dry toilets reduce the potential uses of 
sewage, just as compost is a reduction in the potential 
use of mulch. Dry toilets are quite specifically useful 

• No methane system is used; 

• Sewage is not used in the production of plants; 

• Soils do not suit septic tanks; and 

• Cities have critical water supply problems. 

In using wastewater from kitchen, bathroom, and 
laundry, it is wise to establish just what chemicals, and 
at what concentration, are being released to gardens 
and soils (or waterways). A typical analysis of a 
powdered detergent or a soap could include: sodium or 
potassium salts or poly sulphates, silicates, sulphates or 
bicarbonates, borates, residual biocides (concentrated in 
animal fats) e.g. DDT. Dieldren, Hexachlor from dairy 
cattle, additives such as resins (hardeners), scents, dyes, 
and brighteners, faecal bacteria and viral or worm 
pathogens from washing (in showers or via clothes). 
This data is from Kevin Handreck, CSIRO Division of 
Soils, (pers. comm. 1979). 

Of these, most can be dealt with by soil organisms, 
but if the basic water supply is already saline, sodium 
and potassium salts can add to this and deflocculate 
soil clays or damage leaves (at > 1,000 ppm), while 

borates at >0.5 ppm can create excessive boron concen¬ 
tration in soils, and above 1.0 ppm is harmful to soil life 
and plants. Thus, we need to use plain soaps on crop if 
possible, and route more complex pollutants to tree 
systems (well-monitored), as woody perennials can 
cope better than garden vegetables, and allow more 
time for decomposition of long-term pollutants. 

In critical areas, and especially in arid or delicate 
environments, we may need to create both special soaps 
(unpolluted oils, potash or sodium) and plant special 
crops which remove excesses (many water plants) 
before passing on greywater to the soils and streams. 
There is no blanket policy, only specific cases where we 
can expect to gain yield and also clean up water if we 
know the composition of soils and soaps. 


The only long-term insurance of good water supply to 
a settlement is by rigorous control of a forested 
catchment, including a total ban on biocides and 
metallic processing. As there are few such clean areas 
left in the world, house roof tanks must do for the 
foreseeable future. The 30-40 additives commonly 
introduced into water supplies are often pollutants in 
themselves to that increasingly sensitive sector of 
society developing allergies to any type of modern 
pollutant. These additives represent the end point of 
the technological fix: pollution is "fixed" by further 

Herein, I will stress the biological treatment of 
common contaminants; the only water safe for us is also 
safe for other living things. For millenia we have 
existed on water supplies containing healthy plants and 
fish, and if we keep natural waters free of faecal and 
industrial contaminants, we can continue to do so. This 
is not so much a matter of water treatment, as the 
prevention of polluting activities. 

However, for many existing cities and towns, sewage 

and stormwater supplies must continue to represent a 
"disposal problem". As the wastewaters of upstream 
settlements are the drinking waters of downstream 
areas, our duty is to release from any settlement only 
water of sufficiently good quality to be safely useable 
by others. 

The problem contaminants most likely to affect 
drinking water are: 

• TURBIDITY: silt and fine particles suspended in 
the water. 

• BACTERIAL or ORGANIC pollution from sewage, 
and as decay products, e. g. E. coli, disease organisms 
and viral or protozoan pathogens, parasitic worm eggs 
and so on. 

• METALLIC POLLUTANTS such as chromium, 
cadmium, lead, mercury. 

• BIOCIDES, e.g. Aldrin; Dieldrin; 2, 4-D; 2, 4, 5-T; 
dioxin; PCB. etc (organophosphates, halogenated 

• EXCESSIVE FERTILISER, especially nitrogenous 
compounds, phosphates, sodium and potassium salts. 

• ACIDS or acid-forming compounds (a pH less 
than 5.5 increases metallic pollution). 

Many of these factors interact. Acid rain dissolves out 
of rocks and soil poisonous forms of aluminium, 
mercury, lead, cadmium, and selenium, or other metals 
such as copper, nickel, and lead from drinking tanks, 
tea ums, and hot water tanks. Organisms may convert 
inorganic mercury to organic forms (as happened in 
Minamata, Japan) which are readily absorbed by the 
body. Sewage in water aids such conversion to 
biologically active metals. 

Mercuric fungicide dressing on seeds has not only 
caused direct poisoning of people who have eaten the 
seed, but also poisons the soil. Excessive artificial 
fertiliser increases aquatic biological activity, which 
results in further uptake of metals in acidic waters, and 
so on. In biocides, Aldrin prevents DDT being excreted; 
the combination is deadly (one can buy this mix in 
Australia and the third world, or farmers will achieve it 
by successive sprays. DDT is a stable residual poison 
co-distilling with water, so that distillation will not 
help). An additional threat to public health comes from 

FIGURE 7.31 


Water use in handbasms about equals that lor toilets, so in effect no 
extra, or clean, water is used in toilets; holding tank can contain 
several flushes and excess drains to toilet. 


the many miles of asbestos pipe used in public water 
supply systems; there is a definite threat of both 
stomach and bladder cancer from asbestos particles in 
water supplies. 

Ferric and aluminium sulphate, salt, and lime are all 
added to water to cause fine particles to flocculate and 
settle out as clay. In England, as pH increases due to 
acid rain, and in fact wherever acid rain occurs, 
aluminium goes into solution, and with lead and 
cadmium may bind to protein in vegetables and meat, 
especially those boiled or steamed. Even if salt is added 
to cooking water to decrease these effects, levels far 
exceeding the 30 ug/1 allowable for those with kidney 
problems are experienced. Cooking may increase the 
water content of metals by a factor of 5 due to this 
protein binding, and as well make the metals so bound 
easy to assimilate in the body. Cooking acidic 
substances in aluminium pots simply worsens the 
problem. Aluminium from acidic rain leaching is now 
thought to be a major cause of tree and lake death. 
Ferric sulphate may be safer to use, especially if water 
is initially or reasonably alkaline. Obviously, these 
effects need more study and any inorganic salt or 
metallic salt deserves very cautious use. 


• AERATION (oxygenation) by wind, mechanical 
aeration, or by increasing turbulence in flow. Aeration 
is also achieved by trickle columns and vegetation, 
phytoplankton, or injected air. 

• SETTLING: spreading flow in still-water ponds or 
rush beds to allow particles to fall out, filter out, or 

• SKIMMING and SIEVING to remove large organic 

• FILTRATION via sand beds or charcoal-fibre 
columns, soils, the roots of aquatic plants. 

chemical additives (lime, salt, ferric sulphates) or 
organic (bacterial) gels. 

• BIOLOGICAL REMOVAL by bacteria, phyto¬ 
plankton, and higher plants. 

• pH ADJUSTMENT by adding calcium (as lime) or 
sulphur compounds as needed. 

Filtrat ion 

A classical and widely-used filter is sand. Britain and 
many cities use sand filters followed by chlorination to 

clean settled and treated raw sewage water 
sedimentation. Filtration by slow drip through 1.2 m (4 
feet) of sand (top half fine, bottom half coarse) is used 
even in temporary rural camps for water filtration. For 
cities, fixed sand beds with brick bases are used, the top 
1 cm (0.5 inch) or so of sand periodically swept, 
removed, and dried or roasted to remove organic 
particles before the sand is returned. 

Activated charcoal, often from bones or plants such 
as willow or coconut husks, is also used as a fine filter 
in homes and where purity is of the essence. Fine 
dripstone (fine-pored stone) is used in water cleaners 
and coolers to supply cool water in homes. 

Trickle filters through sand and gravel columns 
actually feed resident bacteria which remove the 
surplus nutrient. In less polluted environments, a 
similar task is carried out by freshwater mussels. 

Carbon is essential for the removal of nitrogen or for 
its conversion by bacteria to the gross composition 
C 5 H 7 N0 2 , and it is generally added as carbohydrate, 
which can be liquids such as methanol, ethanol, or 
acetic acids, many or all of them derived from plant 
residues. This is a bit like "adding a little wine to the 
water” to encourage the bacteria to work. Surplus 
nitrogen is released by bacteria to air. Unless bacteria 
are encouraged and allowed to work, nitrates move 
easily through sub-soils in which no plants or bacteria 
can live, and can emerge in wells and streams. 

In ponds intended for drinking, light exclusion and 
surface water stabilisation reduce both turbidity, and 
thus algae, to a minimal quantity. The stabilisation of 
banks by grasses and clump plants helps considerably. 
Pond surface stabilisers are water lilies, Azolla, and 
water hyacinth. Bank stabilisers are Juncus. Scirpus, 
various grasses and clovers. Phyla nodosa (Lippia), and 
bamboo and pampas grass clumps. 

With turbidity much reduced, filtration loads are 
likewise reduced. Liming will further reduce turbidity 
if pH is 6.0 or less. This is as simple as placing crushed 
marble or limestone as a layer in a tank, or casting 
burnt lime over a pond before filling and (if necessary) 
after filling. Crushed shells or even whole shells in 
water tanks and ponds have the same effect. Lime 
flocculates particles, causing them to settle out of the 

There are several techniques for filtration, some or all 
of which can be used in series. First, trickle filters of 

FIGURE 7.32 

A basic cleanser lor microbiological pollution; flow is upwards from 

base to surface. Surface sands can be washed or roasted for cleaning 
as needed usually every 12-18 months. 


loose pebbles (2.3-10 cm) can be used to form an active 
bacterial surface layer to absorb nutrients, then a sand 
filter can be used to absorb bacterial pollution. Water 
rising through a sand column is fairly clear. 

The shells of water mussels can be substituted for 
pebbles, and the living mussels in the pond or tank not 
only monitor acidity (dying at pH 5.5 or thereabouts) 
but filter, individually, up to 100 l/day, digesting 
bacteria and depositing wastes in the mud base. 
Mussels and crayfish are not only susceptible to low pH 
but are also very sensitive to biocides such as Dieldrin, 
so that their living presence is a constant monitor on 
life-threatening pollution. 

Water, now fairly clean, can be passed through a bed 
of watercress to remove dyes and nitrates, and the cress 
cut and fed to animals or dried and burnt to ash. As a 
final process, the water can be trickled through a 
column (a concrete pipe on end) of active carbon (10%) 
and silicon dioxide (90%), otherwise known as burnt 
rice, oat, or wheat husks. 

The results should be clear, sparkling, safe water to 
drink. No machinery is involved if the system is laid 
out downslope to permit gravity flow 

Lime (freshly burnt) is often used to remove phos¬ 
phorus and sludges in a primary settling lagoon, and 
then water is passed to a trickle tower for ammonia 
removal by bacteria. In towers, of course, the bacteria 
are not further consumed, but in open lagoons a normal 
food cycle takes place, with myriad insect larvae and 
filter-feeders removing bacteria, and frogs, fish, and 
waterfowl eating the insects. In small towns, the water 
can be passed from filter towers to sewage lagoons, 
which in fact may become rich waterfowl and forest 

sanctuaries. It can then be routed to field crop such as 
forest, pasture, and to crops to be distilled or burnt, 
which does not directly re-enter the food chain. 

Sewage Treatm e nt Using Natural Proc esses 
Raw sewage is a mixture of nutrients, elements, heavy 
metals, and carbon compounds; it also contains quite 
dangerous levels of bacteria, viruses, and intestinal 
worm eggs. A typical analysis is given in Table 7.3. 
Units are as mg/1; samples are of 30% industrial, 60% 
domestic wastes at Werribee, Victoria, Australia 
(Hussainey, Melbourne Metropolitan Water Board 
Pubs., 1978). 

Melbourne is a city of 2,700,000 people and its 
sewage lagoons cover 1300 ha (3,700 a.) Thus, there is 
one hectare of pond (in total) to 1,800 inhabitants (or 
about 1 a. for 820 people). In the ponds, raw sewage is 
run into about 724 ha (1,790 a.), where it settles out. 
Each of these primary settling ponds rarely exceed 7 ha 
(17 a.) in area, so about 100 ponds receive and settle all 
raw sewage. Scaled down, this means 1 ha (2.5 a.) of 
settling pond to 3,800 people. 

All these settling ponds are anaerobic, and give off 
biogas, a mixture of methane (CH 4 ), carbon dioxide 
(C0 2 ) and ammonia gas (NH-d, with traces of nitrous 
sulphide or marsh gas (NO ; ). Biogas is, of course, a 
useful fuel gas for engines, or a cooking gas for homes. 
However, it is also a gaseous component of the atmos¬ 
phere that is creating the "greenhouse effect" and thus 
should be used, not released to air. 

The next set of ponds is faculative (as described 
below) and the last set aerobic. These, in total, slightly 
exceed the area of the anaerobic or settling ponds. Most 


are 7-10 ha (17-25 a.) in size. 

Ponds can be built (as they are at Werribee) to fall by 
gravity flow from one to the other. In the first series of 
(settling) ponds, the sludge creates an ANAEROBIC 
condition. In the next series of ponds, some sludge 
passes over and becomes anaerobic at the pond base, 
while the surface water in the pond (due to wind or 
algae) is AEROBIC (oxygen-producing). The final 
series of ponds is totally aerobic. Thus, from intake to 
outlet, we have the terms: 

• ANAEROBIC, or methane-producing (digester 

• FACULATIVE, or part methane, part oxygen- 

• AEROBIC, or oxygen-producing ponds. 

Ponds at Werribee are only an average of 1 m (3 feet) 
deep. Deeper, and the sludge breakdown and wind 
aeration effects are less. 

One thousand townspeople and their associated 
industries therefore need as little as 270 metres square 
of settling pond 1 m deep. We could, in fact, achieve 
this as a "long" pond (or series of ponds) 3 m wide x 90 
m long, or 3 side-by-side ponds 30 m long and 3 m 
wide, or any such combination. We can halve the length 
by doubling the depth to 2 m, and get a pond 3 m x 45 
m long; or treble the depth and condense the pond area 
to a 3 m deep x 3 m wide x 30 m long "digester" pond. 

Such a long and narrow pond is easily made totally 
anaerobic by fitting water seals and a weighted cover 
over the top (which can be of plastic, metal, butyl 
rubber, or fibreglass). Note that for these deeper 
digester ponds we would need to artificially agitate the 
sludge (using pumped biogas to stir it), otherwise it 
settles and becomes inactive (Figure 7.33). 

Sludge is "active" only in contact with the semi-liquid 
inputs of the sewer; thus when we stir up the sludge, 
the better we break down the sewage to biogas. 
Another (critical) benefit in sealed and agitated 
digesters is that no scum forms on the pond surface, 
which can slow the breakdown process further and 
cause an acid condition. 

Of the total dissolved solids (or influent) entering 
such a digester, over a period of 20 days and with a 
temperature of 25-30°C (77-86°F), a very high 
percentage of the mass is transferred into methane; a 
small proportion is also passed on to other ponds, some 
as living cells (bacteria or algae). As methane forms, so 
the oxygen demand of the effluent falls; about a cubic 
metre of methane generated removes about 2.89 kg of 
solids, reducing biological oxygen demand (B.O.D.) to 
that extent. 

In the digester, 90-94% of worm eggs are destroyed, 
as are many harmful bacteria. Useful energy is 
generated, and can be used at that location to run a 
motor for electricity, or to compress gas for cooking or 
machinery (or both, as power demands vary). This 
motor both supplies the heat for the digester process, 
and also compresses the gas for digester agitation, and 
for energy supply. 

What happens in the digester? The marsh gas 

TABLE 7.3 





Total dissolved solids 

1.200 (TDS) 

Bilogical oxygen demand 

170-570 (BOD) 

Suspended solids 


Volatile liquids 


Total organic carbon 


Anionic surfactants 



Nitrite as N 


Nitrate as N 

0.1 -0.3 

Ammonia as N 


Organic N 


Total N 

9 - 56.2 

Orthophosphate as P 


Total phosphorus 




0.09 - 0.35 


0.25 - 0.4 














(as Pt/Cp Units) 



6.9 t 2.0 (near neutral) 

OI the total sewage input, from 45 - 60 % of the 

volume builds up as sludge in settling ponds. 

produced, hydrogen sulphide (H^S), combines with any 
soluble forms of heavy metals to produce sulphides, 
which are insoluble in water above pH 7. A little lime 
can also achieve or assist this result. 

Hussainy found that the following result occurred in 
anaerobic ponds (see original metal content. Table 7.3): 

• Copper is removed 97%, of which 78% was re¬ 
moved anaerobically. 

• Cadmium is removed 70%, all anaerobically. 

• Zinc is removed 97%, 83% removed anaerobically. 

• Nickel is removed 65%, 47% aerobically. 

• Lead is removed 95%, 90% anaerobically. 

• Chromium is removed 87%, 47% anaerobically. 

• Iron is removed 85%, 47% anaerobically. (Up to 92% 
of iron was removed by the faculative pond process, 
but some iron was partly dissolved in the aerobic pond 
again, to give the 85% quoted.) 

The results are that solids, metals, and disease 
organisms are very greatly reduced by the first 
(anaerobic) treatment of sewage. What, in fact, happens 
to the sludge? It becomes methane. In an anaerobic 
shallow pond, or a deeper agitated pond, the more 
sludge, the more active the pond. Thus, a self-regulated 
equilibrium condition soon establishes where input 
balances gas output. If we remove the sludge, the 
process slows down or stops. This is a clear case of 


leaving well alone, of active sludge becoming its own 
solution; rather than being a problem, it generates a 
resource (methane). 

In the anaerobic pond, there are few algae, but there 
are some specialised sulphur-loving bacteria of the 
genera Thiosporallum. Chromatium, and Rhodo- 
pseudomonas. These (in open ponds) may appear pink 
and give thus colour to the ponds. They use hydrogen 
sulphide as a hydrogen source for carbon assimilation; 
their by-product is therefore elemental sulphur (S), 
which binds to the metals present. About 1.8-2.0 mg/I 
of heavy metals are precipitated as sulphides at 1.0 
mg/1 of elemental sulphur. The bacteria help in this 

Passing now to the faculative ponds, we see both the 
life forms and the biochemical processes change. Here, 
algae blooms; four almost universal sewage lagoon 
algae are forms of Euglena, Chlamydomonas, Chlorella. 
and Sceitedesmus. The total algal and bacterial flora (of 
many species) are called PHYTOPLANKTON (plant 

Bacteria are also phytoplankton, the bacteria 
benefiting from the oxygen produced by the algae. 

Typical bacteria in the open ponds are Cyclotella, 
Pinnularia. Hypnodinium, and Rhodomonas. The 
sulphur-loving bacteria may linger on in the sludge 
base of faculative ponds, but are absent or rare in 
aerobic ponds. The algae fix carbon, releasing oxygen to 
the bacteria. 

With such a rich algal food available, ZOO¬ 
PLANKTON now thrive: most are rotifers ( Brachiottus , 
Trichocerca, Haxarlhra, Filinia); cladocerans ( Daphnia , 
Moina, Chydorus, Pleuroxus ); copepods ( Mesocyclops ); 
and ostracods ( Candanocypris. Cypndopsis). Among 
these are protozoan flagellates, ciliates, and some 
nematodes. On this rich fauna, waterfowl and fish can 

Some of the remaining metals are gathered by the 
zooplankton. In mg/1 (dry weight) they contain 1,200 of 
iron, 152 of zinc, 37 parts of copper, 28 of chromium, 
12.2 of nickel, 10.3 of lead, 1.7 of cadmium—almost a 
mine in themselves. Harvested, both zooplankton and 
algae can be added to foodstuffs for poultry. Pumped 
into forests or fields, they provide manures and trace 
elements for growth. In rich algal growth, blooms of 
such forms as Daphnia can be as dense as 100 mg/1. 



I CPARS6- PiU?Afi 1?N. 

2 ACCfc<S0tv Ffccft tfnAfc ftNP 


3 PK£6To£. GP6 To MoTtfc.CoMfSe^P 

«P<& A4l7ATo£_. 

4- Kotor, kum om nenfANe, (on 

MoToBK&O 5 ntti&Z. 



5--io DAY*. 

(Xu«Au) PONJP*. 

4-b PAY5 

\0-1o PAV5 


|o PAY5 

FIGURE 7.34 


A An ideal layout for settlement sewage: yields gas (energy), algae, 
fish, wildlife, crop, and thoroughly cleanses water for release to 
streams. See notes 1-10 on illustration 


These zooplankton masses are self-controlled by eating 
out their algal foods, and can in their tum be eaten by 
fish in subsequent pond systems. 

Of the pH, which varies both long-term and in 
24-hour cycles, it too increases from stage to stage: 
anaerobic pH 6.2-7.8; faculative pH 7.5-8.2; and aerobic 
pH 7.5-8.S. In clogged algal waters at night, it may 
climb higher. 

At the aerobic stage, the B.O.D. is only 3-57 mg/1, 
due mainly to nitrogenous compounds, the suspended 
solids 32-50 mg/1 (now mainly algae and zooplank¬ 
ton). About 80% of these have been removed and 
incorporated into life forms, and the metal levels are 
now down to World Health Organisation standards. 
The water can be used for irrigation, or filtered via rush 
beds to streams. 

Seasonal changes are noticeable. In winter, more 
hydrogen sulphide is given off by anaerobic ponds 
(8-15 mg/1 compared with summer's 2-5 mg/1), and 
winds may contribute more to oxygen levels in open 
ponds than do algae; in winter too, more ammonia 
(NH 3 ) is released to the atmosphere. 

Summer sees residues oxidised to nitrates. The 
oxygen being provided more by algae than by wind, 
less hydrogen sulphide is given off, and there are 
greater ranges of temperature. In winter (10-15°C), 
decomposition slows and sludge levels build up, only 
to be more actively converted in the summer warmth of 
1S-22°C (64-72°F). B.O.D. is 495 kg/ha/day in winter, 
1034 kg/ha/day in summer (at optimum pond 
conditions), showing that activity almost doubles as 
temperature increases. Consequently, almost twice as 
much gas as methane is given off in summer (or in 
heated digesters). In winter, the cooling water of 
methane-powered engines can provide the essential 
heat to digesters via a closed loop pipe. 

In all, this simple lagoon series produces a very 
beneficial effluent from heavily-polluted influent. 
However, there are even more sophisticated biological 
treatments omitted—those effected by the higher 
plants. As outlined below, some genera of rushes, 
sedges, and floating plants can greatly assist with 
removal of heavy metals and human pathogens, but 
perhaps more importantly, some plants can also break 
down halogenated (chlorine, bromine) hydrocarbons 
synthesised as herbicides and pesticides. 

Israel (New Scientist, 22 Feb 79) leads sewage waters 
to long canalised ponds, agitated by slowly-revolving 
paddle-wheel aerators. Ponds are 0.5 m or less deep. 
Under bright sunlight (or under glasshouse covers) 
dense algal mats form, and these are broken up by the 
addition of aluminium sulphate (a pollutant!), skimmed 
off, drained, centrifuged, steam-dried, and fed to either 
carp or chickens (although I imagine that carp could 
self-feed on aquatic algae). Algal protein replaces 50% 
of soya bean protein in feed rations to poultry. Total 
treatment by these methods takes about 4 days. The 
water is alkaline and somewhat anaerobic, needing 
more agitation in winter or on cool days. Holland runs 
sewage to similar canals, and reaps reeds or plants as 

green crop or for craft supplies. 

It has been found (Ecos 44, Winter ’85) that the 
artificial aeration of faculative ponds is most efficient if 
run at intervals of two hours in six (30% of the time). 
The faculative bacteria follow two digestive modes, and 
operate best if a rush of air is supplied after a four-hour 
anaerobic period, excreting carbon dioxide and thus 
reducing the bulk of sludge. There are corresponding 
reductions in energy costs for aeration. Nitrogen was 
reduced from 20 mg/1 to less than 5 mg/1, phosphorus 
from 8.5 mg/1 to less than 1 mg/1 when ferric chloride 
was supplied. The process has been dubbed A.A.A. 
(alternating aerobic and anaerobic) digestion. 

Thus, agitation of anaerobic systems by bubbling with 
compressed methane, and A.A.A. of faculative ponds 
can be used to obtain useful yields of methane and 
high-protein alage from sewage. As for the aerobic 
ponds, such higher plants as water hyacinth removed 
residual metals, surplus nutrients, and the coli group of 
bacilli [New Scientist , 4 Oct 79, p. 29). Microwave 
radiation can also be effective at breaking up algal mats, 
and sterilising algal products, eliminating toxic 
aluminium salts. 

As for temperatures, solar ponds used in conjunction 
with compact anaerobic ponds can supply the low 
grade heat necessary for efficient sludge digestion, and 
methane will drive any motors needed for both aera¬ 
tion and the gas compression used for the agitation of 
sludge. The whole processing system can be made very 
compact, and at the aerobic pond level, throughflow 
can be led to firewood or fuel forest systems, to 
irrigated grasslands (as at Werribee), or via trickle 
irrigation to crops in arid areas. 

Final treatment, now in use in Holland and 
recommended by scientists at the Max Planck Institute 
in Switzerland, can be released via a sinuous, sealed 
canal of a variety of rushes and floating water plants. 

Waters polluted with metals, biocides, or sewage can 
be cleaned by travelling through reed beds of Scirpus. 
Typha, and /uncus; or by harvesting off floating plants 
such as water hyacinth. The rushes and sedges can be 
mown and removed periodically for mulch or cellulose. 
For untreated sewage, a holding time of 10-12 days is 
necessary, or travel through a series of maze-like 
gravel-filter canals with floating weeds and sedges. For 
swimming pools and less polluted systems, a pumped 
"cycle" of water through ferns, rushes, and watercress 
suffices to remove urine and leaves. Such pools need a 
23-30 cm (9-12 inch) coarse river gravel base, with 
intake pipes below, and a skimming notch for leaves. 

Species recommended are: 

• Phragmites communis and spp., Typha spp.: 
Flocculate colloids, dry out sludges, eliminate 

• Schoenoplectus spp.: Takes up copper, cobalt, nickel, 
manganese; exudes mould antibiotics. 

• Scirpus spp.: Breaks down phenols, including toxic 

Low to zero populations of E. coli, coliform bacteria. 
Salmonella, and Enterococci are found after water is 


*anp Piurec (z* peef) serruMt; p*m 

^ RW5H $ tKcW'xrefL p&p 

3 Ht wtsia rwK wit^ 

4- /ftA^e u^6-, w,-^ 

5- PlAg^ToR OR «fl1c TANK £u*-2o P^^TKUv^ 


tti) Z Tt7 W* 6 *T»ft> 

FIGURE 7.35 


From 1-9 includes sand filter; reed canal; settling pond (tank); use in 
house, septic tank; use in glass house and garden; pump return to 
sand filter. 

7 *u*lu y To TRlCKLt lRR\C,\-TiosJ Of ^PeN 
B. PoRe To PTM V/A wimpmiw. PUMP 

treated via the above species. Virus and worm eggs are 
also eliminated. 

Also active in pathogen removal are (although these 
species must be tested and selected for specific 
problems): Alisma plantago-oquatica, Mentha aquatica, 
1 uncus effusus. Schoenoplectus lacustris , Spartina spp.. Iris 

For chlorinated hydrocarbons, use rush types with 
large pith cells ( Aercnchyma), e.g. Juncus spp., especially 
Juncus effusus; Schoenoplectus spp. 

Cyanide compounds, thiocyanates, and phenols were 
treated in fairly short flow times (7+ hours) with 

Systems must be carefully tended and monitored in 
field conditions. Water can flow through a gravel base 

planted to purifying species, or for longer rest times, 
passed through lagoons and ditches. 

Domestically, a comfrey bed is one way to absorb the 
faecal products of animals, where wash-water from 
yards or pens is available. Comfrey can stand heavy 
inputs of raw faeces in solution, and the crop may then 
be used for fodder or trenched for "instant compost" 
under other species of plants such as potatoes. 
Flowthrough systems for methane production take little 
plant nutrient from faecal matter, and comfrey or algae 
ponds deal with the residues, while producing useful 
by-products for compost and stock feed. 

The water from sewage lagoons has been safely used 
to rear beef cattle at Werribee for 35 years, and at 
Hegerstown (Maryland, USA), sewage waters supplied 


to selected coppiced poplar plots can produce (as wood 
chips) some 60% of town energy use. Obviously, water 
saved from reducing the extent of urban lawn systems 
can supply the remaining deficit plus food crop for any 

As waters pass through towns, it may gain from 
300-400 ppm in salinity—a grave factor in usage in any 
dryland area (New Scientist, 13 Oct. 77). Saline waters 
can cause problems in irrigated systems, but algae and 
plant production and removal will reduce this surplus 
salinity. Discharge of sewage to subsoils does not 
remove nitrogen compounds from sewage or farm 
run-off. Again, it is necessary to use productive pond 
production of algae to reduce nitrates to safe levels for 
discharge to soils, or we risk pollution of wells and 
bores, as has occurred in Israel and the USA. 

As with garbage, separation of sewage into solids 
and liquids at the domestic level has productive 
advantages; 2 % urea sprayed on the foliage of rice 
plants in padi has increased grain protein yields to 40% 
(11% protein by weight; New Scientist. 1 Sept. 77). Such 
separation can also be used to recover alcohol and 
chemicals from urine wastes. Urine diluted with water 
to a 5% solution controls moulds on cucurbits, and aids 
garden growth or compost activity generally. 

In summary, it has long been apparent that 
modestly-designed sewage treatment systems based on 

ON % 5FVXS gv/gpy 

FIGURE 7.37 I-1-5*1. 

Developed in South Australia as the 'Arbor system. Supported 
half-pipe never clogs with tree roots, enables trees to remove waste 
water from trench which has cross-supports every 1.2 m to create 
'pools'. _ 


sealed (not leaky) lagoons and their associated 
biological systems not only function to recycle water 
efficiently, but to create a variety of yields from the 
'wastes' of society. There are simply no modern excuses 
for continuing with the dangerous disposal of such 
wastes to seas and subsoils, where they inevitably turn 
up as pollutants in wells, streams, and on beaches, or 
add considerably to the greenhouse effect of 
atmospheric carbon dioxide. It is possible to design 
small and large systems of water treatment systems 
which are both biologically safe and productive. 

C.Qffll L v -V LSgp 1 ic_Tan k Effi ue n t 

There are two basic productive disposal systems for 
septic tank effluent: 

• Underground and surface leach fields around 
which trees are grown. 

• Biogas conversion, followed by a pond growing 
aquatic crop for biogas feed stock, then a leach field. 

A leach field is a trench or open gravelled soakage pit 
through which sewage wastes from a septic tank flows. 
In clays and clay-loams, tank water from a family home 
will stimulate fruit tree growth (without other 
irrigation) for 20 metres or more. The system follows 
normal procedures in that a long trench with a 1:12 
ratio base slope is dug away from the septic tank outlet 
pipe. Topsoil is put to one side, and the trench is fitted 
with an 18 cm or larger half-pipe as per Figure 7.37. 
Coarse gravels or stones are placed in the trench, and 




FIGURE 7.39 ^ £t^\/*T7oNj 

For semi-arid areas Qoes to a 8 x 8 m disposal pit with 0.5 m ot 
0 ravel, straw mulch, trees around pit. Widely used in rural Australia 

over all this a strip of plastic or tarpaper is placed. The 
trench is then back-filled and trees planted 1-2 m off 
both sides as 2-6 m spacing. All fruit and nut trees 

Square or round pits about 25 m square can be dug 
out and filled with graded stone (coarse 6 cm at base to 
2 cm at top). Over this, a layer of cardboard and a thick 
layer of straw is spread, and the latter sown to oats or 
green crop. Around the pit, trees can be planted. 

For biogas applications, septic tank effluent, weeds, 
and manures are loaded into a tank 2 to 1.5 m deep and 
3-4 m in diameter. A loading chute for weeds and 
wastes about 20 cm and 30 cm slants to the base. Septic 
tank effluent also enters at the base. Overflow goes to a 
pond with baffles, and Pitta, watercress, or any 
rampant soft water weed is grown there. These are 
returned to the tank every week. A perforated pipe at 
the tank base is worked by a small gas compressor to 
"bubble" gas back into the tank for 1-3 hours daily on a 
timer. This breaks up the scum on top of the ferment. 
Gas caught in an inverted tank is fed to the house 
cooking range, lights, refrigerators. Surplus from the 
pond is fed to a leach field. 



When thou wilt swlmme In that live bath 
Each fish, which every channel hath 
Will amorously to thee swlmme 
Gladder to catch thee than thou him... 

(John Donne) 

Swimming pools have crept across the affluent suburbs 
so that, from the air, these ponds now resemble a 
virulent aquamarine rash on the urban fringe. The 
colour is artificial, like that blue dye that imitates an 
ocean wave obediently crashing down the toilet bowls 
of the overly-fastidious. Chemicals used to purify the 
water are biocides, and we are biological organisms; if 
fish can t live in our pools, we should also keep our 
bodies out of the water. When chlorine isn’t being used 
as a war gas, it is being dumped into our drinking, 
bathing, and swimming water, where it forms 
carcinogenic chloroform. 

Innovative pool designers now filter natural pools 
below a base pebble bed, using the pebbles as algal/ 
bacterial cleaners, then cycle it through a reed-bed to 
remove excess nutrients before cascading it back, 
freshly oxygenated, into the pool. Such pools can be 
delightful systems with tame fish, crayfish, rock ledges, 
over-arching ferns, and great good health (Figure 7.38). 

They are also reserves for fire-fighting, potential heat 
sources for heat pumps, barriers to fire, and emergency 
water supplies rechargeable from the roof, and can be 
recycled by photovoltaic pumps. Goodbye to the 
endless servicing, and perhaps hello to an occasional 
lobster or overgrown trout! 


Yeomans, P. A., Water for Every Farm, Second Back Row 
Press, Leura, NSW. Australia. 1981. 

_ 7_J_ _ 


On any property, identify sources of water, analyse for 
quality and quantity, and reserve sites for tanks, swales, 
or dams. Wherever possible, use slope benefits tor raise 
tanks) to give gravity flow to use points, and detail 
plant lists that will grow (as mature plants or trees) 

In the general landscape, soil samples (for 40% or 
more clay content) will reveal sites suited to earth-dam 
construction; such sites need to be reserved for future 
storages. A sequence of primary valleys mav enable a 
Keyline system to be established for downhill fire 
control and irrigation. 

Where evaporation exceeds precipitation (arid areas), 
make sure all water run-off is infiltrated to soil storages 
via soil conditioning (rip-lines), swales, pits, or 
sandfield soakages. In humid areas, open-surface dams 
dams can beus«xl. 

Define water "pathways'’ in use, so that water use is 
economical in houses, and that greywater is used in 
gardens (via filtration beds), forests, or (for villages) 
design for clean-up on site through a common effluent 
scheme based on maximum use (methane, plant 
production, irrigation). 

Get good advice on (and supervise construction of) 
all dams. Wherever possible do not impede normal 
stream flow or fish migration, and site houses out of the 
way in case of dam failure. In particular, allow 
adequate stable spillway flow- for "worst case” rain 

Make sure that all earth storages, and in particular 
swales, are planted with trees, to remove infiltrated 
water and (in arid areas) to prevent salting problems. 

Before recommending cloud-seeding, make sure that 
the area to be affected is warned, and that dams and 
swales are designed to cope with any increase (up to 
30%) in rains. 

Design for forested ridges, and maximise forest on 
strategic uplands; do not lend your skills to 
high-country deforestation (or any deforestation). 

Windbreaks and in-crop trees are essential to reduce 
water loss in croplands. 

_ ^8 _ 


Chorley, R. J. (ed.). Water, Earth, and Man, Methuen and 
Co., London, 1969. 

Nelson, Kenneth D., Design and Construction of Small 
Earth Dams, Inkata Press, Melb., Australia, 1985. 

Seidl, Kathe, el al. Contributions to the Revitalization of 
Waters, Max Planck Institute, Krefeld-Hulserberg, West 
Germany, 1976. 


Chapter 8 


The best fertiliser Is the footsteps of the gardener. 
(Chinese Proverb) 

_ 8.1 


The properties and treatments of common soil types in 
specific climatic areas are summarised in later chapters, 
so that in this chapter we deal more with soil as a 
material, including some of the ways to stabilise and 
assist soils in retaining their productivity (soil 
conservation and soil conditioning). 

Soils defy precise treatment, as their structure (and 
permeability), organic content, gaseous components 
(some derived from the atmosphere, some from pro¬ 
cesses within the soil, and some exhaled from the 
sediments below), minerals, pH, and water (or rather 
solute status) changes from hour to hour with soil 
depth and treatment, and in response to micro¬ 
elevations. Added to this is the fact that many soils are 
originally complex mixtures derived from a variety of 
rock types and that they may have had a very long and 
varied history. 

A final factor is that despite all our knowledge, in 
spite of soil services and soil analysis, and despite the 
best attempts of people to care for land, we are losing 
topsoil at an ever-increasing rate. Australia, where 1 
live and write, has perhaps 30% of its original soils in 
fair condition. The rest are washed or blown away, or 
sadly depleted in structure and yield; this is true of 
most countries of the world where extractive 
agriculture and forestry occurs. 

The closer soils are defined, it seems, the less likely 
we are to know them. Notwithstanding this specific 
uncertainty, there are some sustainable approaches to 
soil maintenance and to soil rehabilitation. It is in these 
areas that we will outline strategies. Keep in mind. 

however, that we are always dealing with a matrix or 
mosaic that is in constant variation in place and time. 
Nobody can be dogmatic about any natural system. 

Soil science concentrates very much on what is there 
(classifications), but not on how to evolve soil. Often it is 
left to amateurs—gardeners and farmers—to create 
good soil by water control, modest aeration, and plant 
and animal management. Farmers and gardeners seem 
to be so often the practical, innovative, experimental, 
successful group (while often ignored by academics) 
that I despair of esoteric knowledge ever preceding 
effective action. Very few farmers can persuade a 
group of scientists to assess their apparently successful 
soil trials. It is past time that we assessed whether more 
"science" is not being done by outdoor people than by 
scientists who (like myself) more often collect the 
results of others than generate them by example. 
Science is good at explaining why things work, and 
thus making skills teachable. It is not so good at 
initiating field work, or in training people already in 
the field to work effectively. 

It is hard to say if scientists lack the means to get into 
the real work, or if they choose science to escape from 
field problems. It is hard out in the field of erosion, 
landlords, foreclosures, poverty, greed, malnutrition, 
and exploitation, but that's where all the action is. A 
field approach means choosing values, getting 
involved with people, and inspiring broad scale 
change. Farmers' field days advance knowledge far 
more effectively than scientific papers, and local 
educational sessions more than either of these. 
However, both scientists and farmers have much to 
"give and take". This sort of coalition is slowly starting 
to happen as a result of joint concern on a private level. 

Soils can be RESIDUAL (resting in place over their 
present rock) or TRANSPORTED by water, ice, gravity, 
and wind. In their formation the key factors are rock 
type, climate, and topography (or landform). Water has 
a key role in rock breakdown, combining with such 


common minerals as felspars in rock to swell and 
fracture the rock, then to hydrate the felspars to kaolin, 
clay, and potassium carbonate. The carbonates released 
make of soil water a stronger carbonic acid than it is as 

Atmospheric oxygen dissolves in rain to oxidise iron 
minerals (pyrites) and forms both haematite and a 
quantity of sulphuric acid, which again dissolves 
metals, so that water makes an effective rock 
decomposer, even without invoking the expansion of 
water as ice, or the power of ice (as glaciers) to grind 
rocks to flour. Plants too are wedging open rocks and 
mineral particles, recreating acids, and transporting 
minerals in their sap to other locations. All of this work 
creates a mantle of topsoil, which is estimated to build 
at about 2-4 t/ha per year as uncompacted topsoil, but 
which we remove at a rate of from 40-500 t/year in 
cropping and soil tillage. Even the most ideal tillage 
just keeps pace with the most ideal conditions of soil 
formation, and in the worst cases we can remove 2000 
years of soil in a single erosion season, or one sequence 
of flood or strong wind over cultivated soils. 

The only places where soils are conserved or 
increased are: 

• In uncut forests; 

• Under the quiet water of lakes and ponds; 

• In prairies and meadows of permanent plants; and 

• Where we grow plants with mulched or non¬ 
tillage systems. 

These then are the core subjects of sustainable 
societies of any conceivable future. They are not, you 
might notice, the subjects most taught in the agri¬ 
cultural colleges or forestry courses of the recent past, 
nor do they occupy the minds of politicians, invest¬ 
ment bankers, or TV stars. 

Before starting on the complex subject of soils (and I 
am not a soil scientist), it is wise to draw back a little 
and consider the question of soils from some very 
different viewpoints, or sets of values. They are 
broadly these: 

• Health (both human and plant). We must be 
careful and conservative in approach, especially in the 
area of biocides and high levels of artificial fertilisers. 
After all, our ancestors lived to a ripe old age on 
home-grown produce without the benefit of 
herbicides, pesticides, or artificial fertilisers. We must 
therefore improve on, not lessen, that factor of 
long-tested vitality that was, and is, integral to good 

Not that 1 believe that their health was purely due to 
diet. Several other factors associated with gardening 
may be one day better assessed, including: 

— mild but regular exercise: gardening is a sort of 
steady and non-stressing tai chi. 

— meditation: we can sit and look as much as work, 
and banish all cares. I found my grandfather as often 
just looking as working (and he fed about 20 families 
from his market garden). 

— meaning in gardening, there is a very conscious 
sense of doing a job that is worthwhile, and of direct 

value to others. Gardening, especially food gardening, 
is “right livelihood". 

— life interest, perhaps derived from the above. 
Every day, every season there is change, something 
new to observe, and constant learning. Permaculture 
greatly adds to this interest, and has the dimensions of 
a life-oriented chess game, involving the elements, 
energy, and the dimensions of both life-forms and 
building structures (also with political, social, financial, 
and global implications). 

• Yield . Here, we come to a grave impasse. There is 
no doubt that the once-off yield of a ploughed and 
fertilised monoculture, supported by chemicals and 
large energy inputs, can out-yield that of almost every 
other production system. But: at what public cost? for 
how long maintained? with what improvement in 
nutrition? with what guarantee of sustainability? with 
what effect on world hunger? on soils? and on our 
health? There is now abundant proof that such forced 
yields are temporary, and that plough cultures destroy 
soils and societies. 

These are some very awkward questions to ask of the 
agricultural establishment, for very few, if any, modern 
agricultural systems do not carry the seeds of our own 
destruction. These systems are those that receive public 
financial support, yet they destroy the countryside in a 
multitude of ways, from clearing the land of forest, 
hedgerow, and animal species to long-term soil 
degradation and poisoning. We are thus obliged, by 
entrenched bureaucracies, to pay for the destruction of 
our world, regardless of the long-term costs to be 
borne by our children and our societies. 

• l-ife in soil . Soil organisms are a major soil factor, 
and have myriad perceptible and profound effects on 
pH, mineral content and availability, soil structure, and 

• Ethics . It is not the purpose of people on earth to 
reduce all soils to perfectly balanced, well-drained, 
irrigated, and mulched market gardens, although this 
is achievable and necessary on the 4% of the earth we 
need for our food production. Thus, what I have to say 
of soils refers to that 4%, with wider implications only 
for those soils (60% of all agricultural soils) that we 
have ruined by the plough or polluted by emissions 
from cars, sprays, radioactives and industry. 

Our largest job is the restoration of soils and forests 
for the sake of a healthy earth itself. It is most 
definitely not to clear, deforest, or ruin any more land, 
but first to put in order what we have destroyed, at the 
same time attending to the modest area that we need 
for our survival and full nutrition. 

Without poorly drained, naturally deficient, leached, 
acidic or alkaline sites, many of the plant species on 
earth would disappear. They have evolved in response 
to just such difficult conditions, and have specialised to 
occupy less than perfect soil sites. 

Colin Tudge (New Scientist *86) muses on the 
proportion of the British Isles that could be given back 
to nature. He comes down with a very conservative 
estimate of perhaps 60%. And at that, without letting 


go of the misconception that it is agriculture (not 
individual and market gardening) that will actually 
provide the future food we eat (a common fallacy). 
John Jeavons estimates (on the basis of gardens) that we 
could return perhaps 94% of land to its own purposes. 
Not that I think that we will get there this next decade, 
but we can start, and our children can continue the 
process, and so develop new forests and wilderness to 
explore. A reduction of the ecological deserts that we 
have called agriculture is well overdue, as is a 
concomitant reduction in the twin disasters of 
newspapers and packaging derived from ancient 

_ 8.2 _ 


As long as we live, we will be discovering new things 
about the soil-plant-animal relationship. Soils harbour 
and transfer both diseases and antibiotics; plants will 
take up from the soil many modern antibiotics 
(penicillin, sulfa drugs), and we might then ingest 
them at concentrated levels. Animals will retain 
residual antibiotics (therefore new and resistant strains 
of disease organisms), and will contain residual 
hormones and biocides. Plants and animals may 
concentrate, or nullify, environmental pollutants. Most 
of these pollutants are in fact concentrated by both 
plants and animals, but the degree to which this 
happens varies between species. 

Both dangers and benefits arise from our food. 
Natural levels of soil antibiotics may sustain us, and 
natural resistance to disease is in great part trans¬ 
mitted to us via food. It is certainly the case with 
vitamins and trace elements that they maintain the 
function of many metabolic processes, in minute but 
necessitous amounts. 

When people lived as inhabitants of regions (as 
many still do) they adapted to local soils, plants, and 
nutritional levels or they died out. Today, we bring in 
global food to global markets, and so risk the global 
spread of "agricologenic" (farm-caused) diseases. Like 
the home water-tank, the house garden represents a 
limited and localised risk under our control, and of little 
risk to society generally. Public water supplies and 
commercial foods are a different matter, distributed as 
they are throughout many modern societies. 

In soil rehabilitation, we are forced to start with what 
is now there. Only rarely have we a soil containing all 
the nutrients a plant may need to grow. Most gardeners 
and farmers who have developed sustainable soil 
systems allow 3—1 years for building a garden, and 
5-15 years to restore a devastated soil landscape. This 
applies only to the physical restoration of soils and to 
the development of appropriate plant systems. There 
are far more lengthy processes to be undertaken where 
past chemical pollution has occurred. 

Orchards, sugarcane areas, pineapple, cotton, tobacco 
crop, and banana plantations (to name just a few 
well-known cases) have had such an orgy of mineral 
additives, arsenicals, Aldrin, DDT. copper salts, and 
dioxins applied that even after 18-20 years of no 
chemical use, a set of apple orchards in West Australia 
produces unsafe levels of Aldrin and Dieldrin in the 
eggs of free-range chickens. Attempts to grow prawns 
in ponds on such lands have failed on the basis of 
residual Dieldrin levels in soils. 

When we come to assess the total environmental 
damage caused by persistent misuse of chemicals, we 
will find many farms (as well as bores and rivers) that 
will need to be put into for non-food production (as 
fuel forests or structural timber) for decades to come. 
The same may already hold true for soils within 100 m 
of roadways where leaded petrol is used (and where 
800-1000 cars pass daily). 

We face lock-up periods of tens or at times 
thousands of years for the radioactives blowing off, or 
leaking from, waste dumps and strategic stockpiles of 
yellowcake Uranium (Iowa, Kentucky, Russia and the 
UK or France), or from "accidents" such as those 
occurring at atomic power plants, or from their wastes. 
Cadmium and uranium-polluted soils of chemically- 
based and heavily-fertilised market gardens, waste 
dumps of industry, and the long-term effects of 
nitrate-polluted soil waters can be added to those lists 
of already-dangerous areas. Even now, applied health 
levels would close down many farms and factories, 
and (as awareness rises) this will be done in the near 
future bv public demand. 

The costs of rehabilitation (as for acid rain) already 
far outstrip the profits of degradation, and may in fact 
be prohibitive for areas that were developed for 
farming from 1950 to the present (the age of 
agricultural pollution). 

Large quantities of lead, arsenic, copper, and 
persistent biocides are applied on most apple orchards. 
Data is available for some metals (ECOS 40, Winter 
'84). Copper and lead stay at or near the surface of soils 
in high concentrations. Arsenic may also stay at this 
level in clay soils, or wash down to subsoil (50-80 cm 
deep) in acid sands. Leaching from clays or organic 
profiles ( 10-20 cm) is unlikely, although phosphate 
application may dislodge arsenic to deeper levels. In 
pasture plants under such orchards, copper can reach 
50 ppm (poisonous to sheep). Excess copper in the diet 
causes toxaemic jaundice (liver poisoning) and blood 
in the urine. (People in Australian deserts often show 
high copper blood levels and blood in urine.) 

Molybdenum, zinc and sulphur may buffer copper 
uptake in sheep at least; uptake by plants increases 
with temperature and acidity (for lead and copper), as 
for vegetables. Arsenic uptake is not related to acidity; 
silver beet (Swiss chard) fed with nitrogen lose high 
arsenic concentrations, but may then be unsuitable for 
children due to high nitrate levels. 

Several substances have now polluted soils. There 


are no easy remedies for polluted soils, but the 
following strategies may help: 

• LEAD (from car exhausts and lead paint, pipes, 
battery burning). Worst cases are in urban areas of 
older buildings. Lead at 1,100 ppm can be present, and 
is both taken up by and dusted on the surface of 
vegetables. However, it is possible to garden by: 

— Cracked bricks or gravel as a base. 

— Building up beds to 30 cm deep, and making up a 
rich composted soil of over 40% organic content. 

— Growing vegetables and having leaf analyses 
done; washing in dilute vinegar if lead is still used 
locally in petrol. 

• PERSISTENT BIOCIDES, especially DDT, Aldrin, 
Dieldrin, BHC, etc. If you buy or inherit an old 
orchard, canefield, or plantation (banana, pineapple, 
cotton, tobacco) it is unlikely that any animal product 
(milk, eggs, meat) will be free of high levels of biocides. 
There is no choice but to go into forestry, and to 
produce non-food crop until other methods are 
developed. Also, test your own vegetables for residual 
toxic materials. 

• GROUNDWATER can contain 80-90 biocidal 
substances below farms, including those derived from 
fertilisers, sprays, and fuels. Near industrial waste 
dumps, dioxins, radioactives, and heavy metal wastes 
(cadmium, chromium, mercury) can be added. Do not 
use untested wells or bore waters for any purpose. 
Drink tankwater and try to harvest surface run-off for 
gardens. It is estimated that several decades may be 
needed to clear most aquifers of pollutants. Almost 
every state of the USA has serious problems. Rainwater 
harvest and strict water conservation is indicated for 
the long-term future. Several substances are added to 
town water supplies—and these may include chlorine, 
fluorine, alum (aluminium sulphate) and other 
metabolic poisons. 

We must not add to this mess. Avoid all biocides, 
high levels of nitrates, and watch on-farm disposal of 
oils and fuels. 

The subject of human nutrition is complex, and under 
fairly constant assessment by scientists from many 
disciplines. Four very broad statements can be made: 

1. A normally-mixed diet (omnivorous) has been 
exhibited by most human groups. Excessive dietary 
simplicity, reliance on too few foods, or a restricted 
dietary range has its dangers, while a mixed diet of 
local foods, plus an active life, has usually proved 
healthy, providing good hygiene is also observed 
(public, personal, and domestic). 

2. In the developed countries, refined and processed 
foods, too much inclusion of animal fats, and a 
plethora of food additives has certainly resulted in 
malnutrition and in degenerative diseases (obesity, 
high blood pressure, heart disease). There is now a 
general move away from smoking, heavy drinking, 
and many fatty or processed foods, and a rising 

demand for lean meats, fish, and clean vegetables, 
fruits, and nuts. 

3. In areas subject to famine, semi-starvation, or 
where very low levels of critical vitamins (commonly 
C, A, B-complex) or minerals (iron, zinc) exist, it is 
necessary to take great care with human and soil 
health, and to have a very sound knowledge of the 
possible results of any new dietary change (whole 
grains and pulses may strip out the little zinc the body 
retains where there are starving people in alkaline 
desert areas; zinc tablets may then been needed if such 
foods are commonly used). Traditional diets, long 
maintained, are a guide to local food tolerances. 

4. There is a complex and constant interaction 
between food, soil, trace elements, pH, biocides, and 
fertilisers. Too often, product yield, weight, or 
processing suitability is the only reason given for using 
biocides and fertilisers; nutrition is rarely mentioned in 
plant breeding programmes. Heavy use of 
fertilisers—the macronutrients—can cause a deficiency 
of micronutrients |ApTech 6(1), 19841. 

We are individually different in our ability to 
metabolise and tolerate foods. For some of us, specific 
food allergies are very real, and at least in part (e. g. 
lactic acid intolerance) arise from little exposure to 
certain food groups in our racial history. Individuals 
can test for ill effects by becoming conscious of 
headaches or other symptoms, and experimentally 
eliminating some foods or beverages from their diet, or 
even a class of food (e.g. dairy products, grains), still 
leaving a very wide range of foods from gardens, 
farms, ponds, and nature. 

Another basic individual variable (apart from 
metabolic efficiency) is bodyweight itself. Dosages of 
any substance vary with body build, fats, and dosage 
per kilogram weight, so that alcohol and anaesthetics 
(for instance) may have a very different metabolic 
effect on two people of equal weight, one of whom is 
fat and one lean. So it is with specific foods. 

The sane procedure in health is to maintain basic 
hygiene, grow and eat healthy plants and animals, 
avoid biocides and pollutants, take easy exercise, drink 
clean water or beverages, and stay as cheerful as this 
world permits (or adopt a positivistic lifestyle). The 
rest is up to chance, traffic accidents, or megalomaniacs 
and wars, and these demand commonsense changes to 
the social systems, plus a little good luck. 



From The Ecologist 14 (4) 1984: 

Tribal and traditional people classify their soils on a 
great variety of characteristics based on: 

• Colour (indicates humus content). 

• Taste (agrees with our pH measures). 

• Moisture capacity and water retention. 


• Sand content. 

• General texture. 

• Firmness. 

• Structure (dry soils). 

• Wet-season structure. 

• Vegetative indicators ("health" of a specific crop). 

• Drainage. 

• Slope. 

• Elevation. 

• Animal indicators (e.g. termites: the shape and size 
of their mounds). 

• Plant indicators (for acidity, drainage, fertility). 

• Catena (types of soils based on slope 

• "Hot" and "cold" soils — relative fertility (not 
temperature); can also indicate water retention. 

• Usage, e.g. pigments, pottery, salt extraction from 

• Work needed for crop (an energy input 

• Suitability for specific crop (e. g. yam soil, taro 
soil). Soils can be ranked for up to twelve crop types, 
giving a complex classification. 

• Organic content (apart from colour). 

Thus, sophisticated assessments of soils are available 
from most agricultural societies. However, modern 
classifications are more complex in terms of 
nomenclature and physical categories, and use 
standard colour charts (Munsell and others), standard 
comparisons, standard sieves and so on. 

_ 8 A _ 


Soil is a complex material, and if it has enough 
plasticity (usually clay), or glue or fibre from organic 
sources, it can be pressed or compacted into 
mudbricks, hard pise, or baked to clay or stoneware. In 
any of these forms, it is of little use to plants. 

Uncompacted soils are open, crumbly, or soft unless 
concreted by chemical solutes or compacted by 
ploughs, hooves, or traffic. Crumbly soils have 
nevertheless a definite structure. The soil particles are 
in nodules or clumps held together by roots, clay 
minerals, and chemical bonds. If we speed a plough or 
drag harrows through these fragile assemblies, they 
may powder up as they do in a potter's ballmill, or on 
outback roads. ("Bulldust" is the term used in the 
Australian outback. A soil scientist might speak of 
"snuff".) Dryland soils with a high salt content are 
particularly susceptible to loss of crumb structure, only 
partly relieved by application of gypsum. 

The mantle of soil and subsoil that covers the earth is 
as thin as the shine on the skin of an orange, and this 
mantle extends as living mud below the waters of 
earth as well as on land. It is composed of these 

• MINERALS, mainly silica, oxides of iron and 
aluminium, and complex minerals. 

• SOIL WATERS, fresh, saline, with differing pH, 
and dissolved minerals and gases. 

• GASES, some from the atmosphere, others emitted 
by the breakdown of rocks and the earth's interior. 

• LIFE FORMS, from fungal spores and bacteria to 
wombats and ground squirrels, from massive roots to 
minute motile algae. 

• ONCE-UVING REMAINS; the humus of the earth; 
decayed, compressed, and fossil organic material. 

Soils rarely extend much below 1-2 m, and are more 
often a living system 6-12 cm deep. Subsoils, lacking 
the life components, and buried soils or deep washed 
silts are rare and confined to valley floors and deltas, or 
glacial mounds. 

To estimate the proportion of clay, silt, sand, and 
coarse particles in soil, a sufficient first test (for judging 
the suitability of soil for dam building, mud brick 
construction, and crop types), mix a sample of soil 
from a few typical sites, and pour a cup of soil in a tall 
jar, filled almost with water. Shake vigorously and let 
the soil fractions settle out over a day or a week (clay 
can remain in suspension for up to a week). 40% or so 
clay is needed for dam walls, and less than that for 
good mud bricks (without lime or cement added). 

Of these fractions, the coarse particles are inert, 
although useful in fine soils as a wind-erosion 
deterrent. Sands are 0.05-2 mm, silt 0.05-0.02 mm, clay 
particles less than 0.002 mm (1 g of clay has a surface 
area of up to 1000 times that of 1 g of sand). 

Soil crumb structure, aided by lime (calcium) aids 
the bonding together of these fractions and creates 
20-60% pore space. The organic materials and gels 
hold the structure open in rain, and where plant 
nutrients can become soluble for absorption by roots. 


_ 83 _ 



( Aw/NVMivM, 
iRonJ, ' 




ol assessing crude soil composition; useful lor classification, uses lor 
mud bnck or pis£ work. Soil sample is shaken in v/aler and allowed lo 
stand until layers form (1-20 days). The volume ol each traction 
determines uses and a texture classitication (see FIGURE 8.1). 

Of the 103 known elements, only some are commonly 
dealt with in the literature on soils and water. Soil itselt 
is predominantly composed of aluminium, silica, iron, 
and (in certain shell, sand, or limestone areas) calcium. 
Only mineral ore deposits have large quantities of 
other elements. 

The modified form of the periodic table is given in 
the centrefold of the colour section and a more 
extensive annotation on specific elements is given in 
Table 8.1. It is essential that designers in any field have 
a basic knowledge of nutrients, poisons, and tolerable 
or essential levels of trace elements in food, water, and 
the built environment. 

The health of plants, animals, and the environment 
of soils and buildings are all dependent on the balance 
of elements, radioactive substances, radiation 
generally, and water quality. Of particular concern in 
recent times is the level of radioactives in clays, bricks, 
paints, and stone, and both the emissions from 
domestic appliances (TV, microwave ovens) and 
microwave radiation from TV transmission and power 

Thus, the annotations in Table 8.1 cover a range of 
topics, including short comments on human health. In 
this case we are using the periodic table not as an aid to 
chemistry but as a guide to understanding the role of 
the elements in soil, water, plants and animal tissue, 
and nutrition. 

The colour-coding and the dots on the periodic table 
(see centrefold), plus the following annotations of 


elements give some of their known effects on soil, 
plant, and animal health, or their special uses. 

_ 8,6 _ 


Soils are often analysed as deficient in both PHOS¬ 
PHATES and POTASH in heavily leached areas. 
Phosphates are supplied either by guano (bird 
manures) from dry islands, or from older deposits 
found in sedimentary rock. Potash occurs in the 
mineral kainite, formed in areas of evaporated waters. 
Desert salts usually contains 20-25% potash. 
Phosphatic rock is restricted in distribution, and 
contains 8-15% phosphorus in various combinations 
with oxygen or water (hydrated). There are large 
reserves of potash in common minerals like orthoclase 
(a major constituent of granite). 

NITROGEN can be supplied by water or land plants 
inoculated with rhizobia, or fixed by algae and water 
plants such as Scirpus or Azollti. We can create the 
conditions for fixing nitrogen by growing these 
nitrogen-fixing plants, inoculated with the appropriate 
rhizobia. Much higher levels of nitrogen than were 
previously thought to be available are fixed by land 
plants, in a series of /ones extending from the roots. 
Even after nitrogenous plants such as Acacia. Albizzia, 
and Eleaguu s are cut, the root /one will continue to 
release nitrogen for up to 6 years, so that pioneer 
legumes or nitrogenous trees serve as cover crop for 
trees, and release nitrogen during their lifetimes and 
for some years after. Legumes may not be needed in 
older forests, and typically die out under canopy. Only 
a few larger leguminous trees ( Samanea , Acacia 
melanoxylon) persist as forest trees in a mixed forest. 

Both phosphate (concentrated by seed-eating birds) 
and potash (from burnt and rotted plants or compost) 
can be locally produced if birds are plentiful and their 
manures are used. The phosphates mined from marine 
guano, however, may contain concentrated levels of 
cadmium and uranium, either or both of which (and 
other heavy metals) can be taken up by the oceanic fish 
and shellfish used by marine bird colonies. Continual 
heavy use of such resources is likely to become 
polluting to soils. Our only ethical strategy is to use 
just enough of these resources, and to conserve them 



It makes sense to assume that as soils are leached, and 
so made mineral-poor, these minerals later become 
more concentrated in the sea, in marine organisms, or 
in inland saltpans. Seaweeds, seagrasses, and fish 
residues have always been part of agricultural 
fertilisers, and have maintained their place even in 


modem times. As seawater evaporates, first calcite and 
dolomite, then gypsum and anhydrite separate out; all 
are used for soil conditioning, pH adjustment, or to 
restore soil crumb structure. 

Next, rock salts crystallize out, but only wet tropical 
uplands may actually lack this common nutrient, 
although even there specific plants (often aquatic) 
concentrate salt which can be gathered or leached from 
their ashes. 

Lastly, potash, magnesium salts, and a host of minor 
elements remain; the evaporites (those already 
deposited) being the most soluble and therefore earliest 
deposited. The liquid that remains after the common 
salt content deposition is a rich source of minor 
minerals and trace elements. It is, in fact, sold as 
"bitterns” (bitter oily fluids) for dilution and 
incorporation in crop soils, or in low concentrations 
(diluted 100-500:1) used directly as foliar sprays in 
strengths varying from 1-20 1/ha. Very corrosive, 
bitterns (which include bromine and many of the early 
elements of the periodic table, plus some rare 
minerals), are safely held and distributed only via 
non-corrosive vessels and pipes (today, polyethylene 
pipes and drums). 

Bitterns are cheap, and easily transported to leached 
areas, but their effects must be established by local 
trials on specific crop. As these evaporites are so easily 
dissolved, they are also those most likely to be carried 
to sea in rains. 

Rocks and rock dusts 

Granites contain felspars yielding potash or sodium 
salts. Limestone and dolomite yield calcium and 
magnesium, and mineral deposits or their ores give 
traces of the basic minor elements. Of these, calcium (in 
all but highly calcareous areas) is most needed, 
dolomite (except where magnesium is already in high 
ratio) is next; phosphates and felspars follow, along 
with trace elements in small quantities (as low as 5-7 
kg /100 ha for zinc, copper, cobalt, and molybdenum). 

Field trials have established that cheap ores, finely 
ground, are as effective as more refined sulphates or 
oxides (Leepcr 1982). Sometimes such minerals are 
given to animals as salt licks, in molasses, in water, or 
as injections or "bullets" of slow-release elements 
(cobalt) in a pellet which lodges in the rumen. Some 
mineral elements also reach plants via urine, but foliar 
sprays are more rapid-acting and effective. 

Fine rock dusts of a specific rock suited to local needs 
are often cheaply available from quarries or gravel pits. 
Basalt dusts are helpful, for example, on leached 
tropical soils. Rock phosphate contains 8-15% 
phosphorus, but is very slow to release nutrient, and 
may in fact be absorbed completely on to leached clays 
and clay-loams. Super-acid phosphate added to 
compost, or to plants used in compost, may be 
necessary under such conditions. Rock dust as an 
unselective category can do as much harm as good on 
soils, adding excessive or poisonous nutrients in some 
cases, or excessive micronutrients. 

_ SJ _ 


There seem to be two important determinants of the 
concentration of elements or nutrients through the soil 
profile (that vertical column of soil from the surface to 
2 m or so deep). The first is the penetration of water. 
Water is a universal solvent, enabling compounds to 
dissociate into ions, and transporting them, firstly, to 
various deposits at microsites in the soil. This effect 
works in three dimensions: 

• Water travels by infiltration to varying depths, 
soaking in from the surface down. 

• Water can also rise from the soil water table 
upwards, either by flooding, by capillary action 

Icontinued on page 195...I 


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TABLE 8.1 


1. Hydrogen (H) is an extremely mobile and reactive 
gaseous element; the number of free ions of this 
element determine the pH of soils, together with the 
hydroxyl (OH*-) radical in alkaline areas. Hydrogen 
combines with several other elements and organic 
substances to form acids. It is a potentially inflammable 
light gas. now replaced by helium in balloons and 
airships. Some plants, especially algae and rushes, 
can transpire hydrogen, and in so doing break down 
the halogenated hydrocarbons that are used in 
pesticides and herbicides. 

Hydrogen combines with oxygen as hydroxyl (OH?) 
or water (H,0). the basic gaseous and liquid elements. 
It is the concentration of H* or OH? ions in solutions 
that decides the pH of soils and water. Hydrogen 
combined with carbon as methane (CHJ is emitted by 
decaying humus in anaerobic (airless) environments 
such as under water or in compacted or boggy soils. 
Such soils usually have a mottled profile, and are often 
bluish, yellow, or contain iron stains and nodules. 
Methane is a component of marsh gas, or biogas from 
digesters, usually associated with carbon dioxide and 
sulphur dioxide (the gases of decomposition). A 
sulphurous smell in subsoils is a guide to wet-season 
water-logging, and should be noted for plants 
intolerant of stagnant waters. 

3. Lithium (Li), the lightest metal, is prescribed 
medically as tablets in cases of hyperactive and 
disturbed people; it may moderate nerve impulse 
transmission across synapses. Lithium is found in plant 
and animal tissue. 

5. Boron (B) is a trace element, necessary to (e.g.) 
the brassicas and beets. As many detergents also 
contain boron, boron pollution or poisoning can build 
up in gardens and affect plant health adversely. Use 
soap, especially in drylands, where citrus and grains in 
particular can be boron-poisoned in dry seasons. 
Borax at 160 g/ha is used on beet and Brassica 
(cauliflower, turnip) crops where soil levels are low in 
boron. Boron seems to be essential to the transport of 
sugars in the plant, to pollen formation (hence, fertility), 
and to cell wall structure (like calcium). 

Borax is poisonous to seed and to insects, and is 
used with dilute honey as an ant and cockroach 
poison. Sea sediments (and the sea) contain high 
boron levels. Surplus boron can cause anaemia in 
people. In soils. 0.75 ppm is ideal, but 1.0 ppm can be 
toxic to plants. It is likely to be at toxic levels in dry 
years, where soils have been derived from marine 
sediments (Rural Research. CSIRO, Autumn ’86). 

6. Carbon (C) is the basic building block (with 
hydrogen, oxygen, as hydrocarbons) of life forms. It is 
added to soils as humus, compost, and mulch. Pitted 
or buried wastes need nitrogen or oxygen, therefore 
air, for decomposition. 10-20% humus ensures good 
structure in both clays and sands. More than 50% 
humus inhibits uptake of polluting heavy metals (lead) 

cities; less than 7% may not improve soil structure 
unless calcium is added. 

Carbon combines with oxygen to form carbon dioxide 
gas. which is released from agriculture, forest felling, 
and industry to create the greenhouse effect and 
subsequent earth heating; this may be a critical 
adverse factor for human survival on earth. Plant trees, 
do not use bare fallow, and add humus to soil. Carbon 
in soils is about 58% of organic matter (combustible), 
existing mostly as colloids (assess nitrogen and 
multiply times 20 to obtain the carbon content of soils). 

7. Nitrogen (N) is a major plant nutrient. 80% of the 
air itself. Legumes and many non-legumes (alder. 
Casuarina) that have root associates (fungi, bacteria) 
will fix nitrogen from air if molybdenum is present as a 
catalyst to convert nitrogen to ammonia. Nitrogen as a 
foliar spray of urea can, however, increase the protein 
content of grains such as rice by 40%. 

Nitrogen is part of all amino acids (hence proteins), 
of chlorophyll, and of enzymes. It is very mobile in 
plants, and has dominant effect on other nutrient use. 
or uptake. Plants absorb nitrogen in the form of nitrates 
or ammonium, and the plant coverts this to ammonia to 
create proteins. 

In water or with bacteria, nitrogen forms NITRATES 
which at low levels are benefical, but at high levels 
(more than 80 ppl) are lethal to young animals and 
children. Also, mouth bacteria and sewage bacteria 
turns nitrates into NITRITES, hence NITROSAMINES 
which are cancer-associated. Nitrates are building up 
in all soil waters below agricultural land, and occur 
naturally in many desert bore waters. Thus, fertilise 
plants in the garden at minimum nitrogen levels; do 
not use heavy doses of nitrogen fertilizer, but rather a 
modest legume interplant. Check water levels for 
human health, especially in deserts. 

Too much animal manure also releases surplus 
nitrogen. Thus, reduce cattle and run them on 
pastures, not on feedlots. Dispose of sewage in forests 
to aid in tree growth. Constantly measure nitrate levels 
in leaves, water, soil. In particular, do not inflict high 
nitrate levels on people with malnutrition; they can be 
killed by an excess of nitrate in their food. Accepted 
levels in Europe (E.E.C. standard) are 50 mg/1 in water 
(50-80 ppm). These levels are being exceeded where 
nitrate fertilisers and even natural manures are spread 
on soils; ammonia from cow dung is now 115,000 
t/year in Holland, accounting for 30% of the acid in rain 
from Dutch sources (AZS. 6 Feb '86). In humid areas, 
70% of human intake is from vegetables, and 21% 
from water. 


0-50 Safe for human consumption 
500 Spinach grown from compost 
2.000-3.000 Chemical fertiliser-grown spinach 


8. Oxygen is a necessary lor respiration (energy 
release in blood). Soils also need oxygen (air) and thus 
good open structure and soil pores as 12-30% of the 
soil bulk. Aeration in soils is achieved by using calcium, 
trees, worms, ripping, humus, or sometimes by blowing 
air through sub-surface irrigation pipes. 
WATER-LOGGING reduces pore space and thus root 
oxygen. Crops such as walnuts, oranges, chestnuts, 
and potatoes require deep loose soil and plenty of 
oxygen. Pear trees and marsh grasses (Yorkshire fog, 
Imperata grass) require much less oxygen and can 
grow in more compacted or wet soils. Soil loosening 
and draining (conditioning) improves oxygen supplies 
to soils. Soils need to have good open pore spaces to 
1-2 m (3-6 feet) deep. Large soil pore spaces are only 
achieved by soil life and perennial crop. 

9. Fluorine. Although beneficial in small amounts, 
as in seaweed fertiliser, it is a serious poison at high 
levels. It is commonly found in bore water, or in 
downwind pollution plumes from metal processing 
works (zinc, aluminium, copper), causing bone 
deformation in animals, stunted growth, and serious 
metabolic disturbance. Check water, especially bore 
water, for high levels and use tanks for drinking water. 
Fluorine is useful at very low trace levels only. Surplus 
can cause anaemia; high levels are found in (e.g.) 
marine phosphate deposits, hence fluorine can be high 
in fertilisers derived from these. 

The fluorine level sufficient for normal growth and 
bone develoment is about 1 mg/day. Tea drinkers 
ingest this from tea leaves; as the chief source is in 
water. 1 mg/I (1 ppm) is sufficient. Seafoods (fish, 
oysters) can contain 5-10 ppm fluorides. 

Problems of excess flourine occur where dusts from 
mineral processing fall out on vegetation, where ‘hard’ 
waters (common in deserts) contain more than 1 ppm 
fluorine (actual levels can reach 14 ppm) and where 
diet is mainly seafood. The bones, spine and ligaments 
can become calcified in areas where excessive flourine 
is present in the diet. Teeth may be 'case-hardened' 
by flourine, and show little outer sign of decay while the 
tooth itself rots. 

11. Sodium (Na). With chlorine, it makes up 
common salt. At low levels, it is necessary to plants 
and animals, cell health, and function of the nervous 
system. At high levels, sodium causes collapse of soils 
and loss of pore space, displaces calcium and 
disperses colloids. Beets and some other crops need 
adequate levels, likely to be absent or low in wet 
tropical uplands only. Elsewhere, enough sodium 
comes in with rain as salt crystals in raindrop nucleii. 
Real problems occur when soil salts are mobilised by 
irrigation, potash fertiliser, or soil flooding in dryland 
areas. Excessive salt causes circulatory and kidney 
problems in people, especially those in sedentary 
occupations. Salt in vegetable cooking water blocks 
uptake of some heavy metals on plant proteins, so if 
lead pollution is suspected, add salt to cooking waters. 

12. Magnesium (Mg) With calcium it is found in 
DOLOMITE. It is needed by plants, and common in 

most subsoils. It forms the central atom of the chloro¬ 
phyll molecule, activates enzymes, and concentrates in 
seeds. Like nitrogen, it is very mobile in the plant. 
Magnesium is likely to be deficient only in sands and 
sandy soils; it is present in the clay fraction of soils, 
and is released by soil acids and humus. It is supplied 
by dolomite application on farmlands, as tablets of 
dolomite for animals, and mixed in animal foodstuff. 
Magnesium carbonate from dolomite buffers plant and 
soil acids, as does lime, but it can cause plant 
poisoning if not balanced by high lime (calcium) levels. 

Magnesium is essential for chlorophyll and in the 
mitochondria of human cells, hence energy metabo¬ 
lism. It is present in all green plants. Deficiencies do 
not normally occur where people are healthy and are 
not subject to diarrhoea; when required by people it is 
given as an intravenous fluid at 10 minimoles per kgm 

13. Aluminium (Al). A 'Jekyll and Hyde' element, it 
forms a large part of soils and red clays (with iron), or 
as poorer bauxitic dryland deposits. It is poisonous as 
aluminium sulphate, formed in acid rain or sulphur- 
polluted soils, e.g. in industrial areas, and is also 
released when cooking onions in aluminium cookware! 
Heavy aluminium silica uptake in humans may assist 
the development of senile dementia, thus calcium in 
the soil and as tablets is a partial defence. Some areas 
are naturally high in acid-aluminium soils. An adequate 
level of calcium is needed in all gardens, and even in 
rainwater tanks (as marble or limestone chips, whole 
sea shells, gravels of lime). 

Avoid aluminium utensils (use iron, enamel, stone, 
steel) if cooking salty, acid or sulphurous substances 
(vinegar, onions). Soluble aluminium in concentrations 
of 0.1 to 1.0 ppm is tolerable, but above this level 
susceptible plants start to die. At 15 ppm or higher, 
many plants die. 

14. Silicon (Si) is an important part of cell walls in 
many grasses, bamboo, and is essential in soil cation 
exchange capacity of deep, red, heavily-leached tropic 
soils (an application of cement dust can assist this 
exchange). Pine trees and conifers generally are poor 
nutrient recyclers, and can produce nutrient-deficient 
silica soils under their litter, thus losing calcium and 
other elements to leaching. Therefore, use grasses and 
broadleaf. leguminous, or soil-building trees with 
conifers. Many trees deposit salt, phosphorus, 
manganese, zinc, potash, etc. at high topsoil levels due 
to good nutrient recycling via leaf fall. Silica is normally 
at 20-40 ppm in soil waters, and in highly alkaline, wet, 
warm areas can be leached away altogether, hence the 
use of cement (calcium silicate) to restore some silica 
to plants; in such areas, tree crops are the only 
sustainable solution. 

Silicates make up much of the bulk of normal soils, 
but very high silica in rock may produce acid soils in 
high rainfall areas (silicic acid). Bamboos are good 
sources of calcium and silica as a garden mulch in the 
tropics. In ponds, diatoms need silica to proliferate; 
these are an excellent fish food. 


15. Phosphorus (P) (as phosphate) is an essential, 
common plant element, recycled by many trees and 
fixed by the root associates of several trees 
( Casuarina . Pultenea, Banksia), by algae, in the mud of 
ponds, in bones, and in freshwater mussels. High 
phosphate levels in bird manures are derived from fish 
bones and seeds. Phosphorus is essential to the 
energy metabolism of plants, hence photosynthesis 
and respiration. Cell divison, root development, and 
protein formation are regulated by phosphorus. It is 
highly mobile in plant tissue. 

In some oceanic guano deposits, phosphates can 
be contaminated by cadmium, mercury, uranium (40 
ppm) and fluorides. All heavy cropping demands 
phosphate for production, and there is a general world 
soil phosphate deficiency, especially in poorer 
countries. Most western soils are now over-supplied, 
with a very large unused soil bank of phosphorus, 
hence with the pollutants of phosphatic rock. Cadmium 
levels in inorganic market garden crop may commonly 
exceed health limits. 

Bird islands, areas of recent volcanic ash. and some 
soils over phosphatic rocks are not phosphate- 
deficient. Sandy, bare-cropped. wet. and water¬ 
logged soils, old soils, and alkaline soils may show 
deficiencies. On the latter, try sulphur to adjust availa¬ 
bility. Super-acid phosphates are used to make 
phosphate available to plants, albeit expensively. Most 
soils (superphosphated since the early 1950's) may 
have 750 ppm in the top 4 cm, and most of the rest of 
the applied phosphate is bound up and unavailable in 
the top 20 cm. Only on deep, coarse, leached treeless 
sands with heavy rains or in bare-soil fallows is a lot of 
phosphate lost. Drainage water contains 0.2 ppm in 
clay or loam soils, a minute loss. In natural systems, 
phosphates are supplied by fish and bird manures. 

Calcium, iron and aluminium immobilise phosphate; 
a pH of 6-7.5 releases it. Basic superphosphate (phos¬ 
phate and lime) finely ground is available (soluble) to 
plants. The home gardener can use bone dust, 
phosphate and lime, and mulches, which are all 
effective. About 45 ppm phosphate in soil is needed for 
grains (optimum pH 6.0-6.5). Pelleting seeds with 
basic superphosphate provides phosphorus. In soils, 
phosphorus combines with iron, aluminium and calcium 
as insoluble compounds, and with living materials or 
humic compounds as “available phosphorus". Despite 
folk stories to the contrary, superphosphate has not 
been found to acidify soils (unlike ammonium 

Phosphate levels (“native phosphate") fall with depth, 
and are low in most subsoils. Generally, to increase 
phosphate availability, try humus in warm wet areas, 
sulphur in drylands, and adjust pH elsewhere with 
calcium (lime or dolomite). For trees, apply light 
phosphate dressings regularly in sands. Phosphorus 
deficiency reduces growth in animals by depressing 
their appetite for herbage. 

Of all the elements of critical importance to plants, 
phosphorus is the least commonly found, and sources 

are rarely available locally. Of all the phosphatic 
fertilisers used. Europe and North America consume 
75% (and get least return from this input because of 
overuse, over-irrigation, and poor soil economy). If we 
really wanted to reduce world famine, the redirection of 
these surplus phosphates to the poor soils of Africa 
and India (or any other food-deficient area), would do 
it. Forget about miracle plants; we need global ethics 
for all such essential soil resources. As long as we 
clear-cultivate. most of this essential and rare resource 
will end up in the sea. Seabirds and salmon do try to 
recycle it back to us. but we tend to reduce their 
numbers by denying them breeding grounds. 

Unpolluted phosphate deposits are found only in 
limited areas, in sedimentary rock. Trees do mine the 
rare phosphorus released by igneous rocks, and they 
are responsible for bringing up phosphorus to the 
topsoil wherever it is rare in more shallow-rooted 

About 15-20% of the inessential use of phosphorus 
is in detergents. The older potash soaps are the 
answer to that sort of misuse, or the recovery of 
phosphorus from greywater rather than a one-way trip 
via a sewer to the sea. Uncut forests may lose 0.1 
kg/ha/year, while clear-cropping can lose 100 kg/ 
ha/year or more, a 1000 times increase in lost 
minerals, never accounted for in logging and clearing, 
or added to the cost of woodchipping and newspapers. 

Phosphorus is found concentrated in seeds and in 
the bones of vertebrates, especially fish, in mussels 
(freshwater) and the mud they live in. and in the 
manures of animals eating fish, seeds, and shellfish. 
Bone meal from land animals is a traditional source, 
and most farms (up to 1940) kept a flock of pigeons as 
their phosphate factory, while in aquatic cultures, 
phosphorus was recovered from the mud of ponds 
stocked with mussels and from fish and waterfowl 
wastes. Bat guano is also a favoured source of phos¬ 
phate in Holland. Even a modest perch in a bare field 
will attract a few perching birds to leave their 
phosphates at a tree or along a crop line. 

Conservation farming (Cox and Atkins. 1979, p. 323) 
loses about one-half to one-third the phosphorus of 
contemporary agriculture, even without non-tillage. 
Non-tillage farming would lose even less, but is rarely 
assessed except in dollar yield terms. Bioregional 
farming, and home gardening with wastes returned to 
soils would lose even less; and finally, regional food 
supply, waste recycling, and a serious consideration of 
devoting 30% of land surface to trees might just be a 
sustainable system. Next to clean water, phosphorus 
will be one of the inexorable limits to human occupancy 
on this planet. We must not defer solving these 
problems or conserving our resources any longer, or 
we betray our own children. 

16. Sulphur (S). Many anaerobic bacteria 
(thiobacilli) fix sulphur, which is why anaerobic ferment 
of plant and animal materials is rich in the sulphur- 
based amino acids, and of high nutritional value. The 
sulphur oxidised by anaerobic bacilli also removes, as 


insoluble sulphates, most heavy metals from such 
flow-through systems as sewage digesters. Some 
thiobacilli occur in all warm wet soils, and many can 
operate down to pH 1.0! With ammonium sulphate, 
soils tend to become acidic and so reduce plant yields. 
Sulphur is used in drylands to reduce pH and so make 
iron, zinc, and trace elements available. Clover, in 
particular, may show sulphur deficiency in the 
sub-tropics (wet summers). 

Sulphur is part of all proteins, and is present in the 
body as the two amino acids methionine and cystein. 
The vitamins thiamin and biotin contain sulphur. Food 
intake by people is from the amino acids, and 
deficiencies do not occur if meat protein is sufficient, or 
if anaerobic ferment of leaf materials is part of food 
preparation. Many vegetarians get their animo acids 
from yeasts or bacteria rather than from fresh plant 

17. Chlorine (Cl) was used as a war gas. and today 
to "sterilise" waters; it is a dangerous gas to inhale. 
Chlorine is used by plants, and is normally available as 
salt. It is a trace element, and used only in minute 
amounts. It concentrates in crop. e.g. 350 ppm in soil 
gives 1000 ppm in crop. In water, and in contact with 
organic materials, it releases chloroform, a carcino¬ 
genic gas. Avoid chlorinated water if possible! 

19. Potassium (K) is used in large quantities by 
plants. It is usually plentiful in and areas. Potassium is 
deficient on sandy, free-draining coast soils. Not much 
is removed by livestock, but potatoes, beans, flax, and 
the export of hay may remove soil reserves to below 
plant needs. It is readily absorbed on colloids, and is 
usually plentiful in clays, especially illites. not in kaolin. 
Gardeners add ashes, bone, natural urines and 
manures or green crops for supply to heavily cropped 

Earthworm castings commonly concentrate potash 
(at 11 times soil levels). Excess potash fertiliser can 
greatly increase soil sodium, and so block calcium 
uptake; beware of this in alkaline or dryland soils. 

20. Calcium (Ca) is needed in all soils, and is 
removed by sodium in drylands. Even where calcium 
exists in an alkaline area, sodium may suppress its 
uptake by plants. Sometimes, gypsum is applied (30 
tonnes/ha) and the excess sodium then removed by 
flushing out as sodium sulphate. Plants need large 
amounts of calcium. It is an essential part of cell walls, 
enzymes, and in chromosome structure. 

The proportion of the four major ions in ideal 
agricultural soils should be about: Calcium: 
Magnesium: Potassium: Sodium (50:35:6:5) 

Note that adding potassium can increase sodium, 
that sodium is antagonistic to (displaces) calcium, and 
that magnesium ions should always be less than 
calcium ions. Do not add too much dolomite if soils (as 
clays) already contain adequate reserves of 

Many peoples have lactose intolerance and cannot 
get calcium on a milk diet, so lime or dolomite on 
gardens or as tablets may be needed. Calcium is lost 

(excreted) in stress, and needs replacement after 
periods of prolonged stress. Low calcium areas 
produce predominantly male farm animals and humans 
(as a primary sex ratio), and lack of calcium produces 
skeletal and metabolic malfunction. 

Calcium phosphate is the chief mineral constituent of 
bones. Bony tissue is always losing and gaining 
calcium, but older women, in particular, suffer bone 
fractures from loss of calcium in the ageing process; 
immobilised limbs also lose calcium. Gross calcium 
and vitamin D deficiency results in rickets. 

22. Titanium (Ti) is not a nutrient, but in sands and 
the presence of sunlight it acts as a catalyst to produce 
ammonia for plants, often combined with iron (TiFe) 

( N.S . 8 Feb 79. 8 Sep '83). Ammonia is provided at 
50-100 kg/ ha/year. Rain and moist soils make this 
available to plants—a useful desert strategy. 

24. Chromium (Cr) is a poison to plants and 
animals, occurring in serpentine rock. It is used in the 
preservation of timber, and is to be guarded against 
from electrolytic and leather works as it poisons active 
biological agents in sewage works. It is easily removed 
or recycled at the source. 

As some chromium occurs in all organic matter, it is 
in fact a trace element, related to glucose tolerance in 
humans, and necessitating insulin if absent or in very 
low quantities. Very little firm knowledge of the 
metabolic function of chromium is available. 

25. Manganese (Mn) is a readily available trace 
element on acid soils, except in sands. It may cause 
manganese poisoning below pH 6.5. On alkaline soils, 
or when pH exceeds 7.5. it may be deficient in grain 
crop or vegetables, but seed soakage. seed pelleting, 
or foliar sprays supply this nutrient. Even flooding at 
periods will mobilise manganese. A typical deficiency 
situation occurs on poor sands heavily dressed with 

Bacteria fix insoluble manganese, and can create 
problems in pipes and in concrete water raceways 
even at 2-3 ppm manganese. Aluminium sulphate 
(from acid rain on soil) may mobilise manganese, 
mercury, cadmium to lethal levels. Manganese 
leaches out of acid soils, deposits in alkaline horizons 
as manganese-iron concretions, and on sea floors as 
larger nodules. 

26. Iron (Fe) is normally plentiful in soils, and is a 
critical element for plants and animals. Plants can 
show iron deficiency symptoms in alkaline drylands or 
on heavily limed garden soils. Sulphur in gardens, or 
iron chelates, remedies this situation; iron can also be 
added as small amounts of ferric sulphate. Deficiency 
causes interveinal leaf yellowing in plants, and low 
blood iron in people (anaemia). Ferrous iron spicules in 
soil assist the formation of ethylene. Ferric iron (oxides) 
are "unavailable" (F>0 3 ). Iron concretions and iron 
staining in sands are often associated with microbial 
action along plant root traces. Iron-deficiency anaemia 
in people is a common problem in deserts, or after 
blood losses in menses or dysentery. 

In humans, blood iron is as important in energy 


transfers as is copper in invertebrates. Deficiencies are 
normally rare but must be watched in women of 
reproductive age. when lack of iron is widespread and 
causes ill-health and lassiitude; anaemia also occurs 
in infants and children. Meats such as veal, liver, and 
fish eaten with soya beans, lettuce, parsley, maize, etc. 
can provide dietary iron. Meat and ascorbic acid 
(vitamin C) increase iron absorption from food. Iron in 
bone marrow is needed for new blood cells. Clinically, 
ferrous salts ingested can be used in cases of 
excessive blood loss. 

People brewing beer and wine or cooking cereals in 
iron pots often ingest excess iron. Alcholism and 
diabetes exacerbate iron excess, although excessive 
iron is an unusual condition. 

27. Cobalt (Co) Copper and cobalt can be deficient 
on poor coastal sands. Cobalt is necessary to many 
legumes, and especially needed by livestock, who are 
■unthrifty' if it is deficient, as it can be in highly alkaline 
areas. Only an ounce or two per acre is needed, and 
this can be supplied as a cobalt -bullet" in the rumen of 

Cobalt is necessary for synthesis of vitamin B, 2 in 
ruminants; if deficient, further metabolic problems then 
occur. Often diagnosed via B, 2 tests on blood levels. 
Deficiency can cause anaemia. Toxicity can occur if 
excess is ingested. Radioactive cobalt is a serious 

28. Nickel (Ni) is not noted as a plant nutrient or 
poison, but with copper can intensify poisoning in 
people, e.g. in office rooms using urns, or in mining 
areas. Many people demonstrate skin reaction (rash) if 
nickel is used as bracelets. 

29. Copper (Cu) is a necessary micronutrient which 
can become a poison at higher concentrations. Copper 
in plants is an enzyme activator, and is concentrated in 
the chloroplasts of leaves. Copper is deficient on 
shell-grit dunes, acid peaty soils, coastal heaths over 
poor quartzite sands, and in deeply weathered basalts. 
Black sheep are good indicators, and if deficient 
develop whitish or brown wool, or white-coloured 
sheep will grow "steely" wool. Copper sulphate at 1 kg/ 
ha every 5 years is a cure. Old stockmen put a few 
crystals into water-holes. Deficiency (with iodine) can 
lead to goitre (thyroid inbalance) and anaemia in 
animals. Levels above 12 micromoles/1 are excessive 
in drinking water. High blood copper levels in deserts 
are often as a result of zinc deficiency. 

While copper deficiency is rare or absent in adults, 
copper toxicity is of more concern especially where 
copper sulphate is used to clear algae from drinking 
water, and also from foods or water standing in or 
boiled in copper utensils and pipes. Copper poisoning 
is serious, with liver deterioration (cirrhosis) and brain 
effects (tremors, personality changes). Once hopeless, 
such cases can now be somewhat alleviated by 
chelating agents. 

30. Zinc (Zn) is deficient on leached sands, dunes, 
alkaline sands, and supplied by zinc sulphate spray on 
plants or zinc salts in seed pellets. It should be tested 

for in all desert gardens. Zinc is critical for both tree 
establishment in many deserts or dunes, and to human 
health, and is cheap to supply. In plants, zinc is 
essential to the growth control hormones. 

Zinc deficiency causes gross metabolic imbalances 
and stunting of growth. People with malnutrition often 
have low zinc blood levels and poor wound healing. 
Diabetes is often linked with zinc deficiency. Excessive 
zinc acts as an emetic, causes vomiting and weakness. 

Zinc is necessary to several enzymes in the body; 
prostate (hence seminal) fluids are high in zinc. Diets 
of coarse grains, unleavened bread, and low meat 
intake contribute to zinc deficiency in poor people, 
especially in high-calcium soils. Oral zinc sulphate can 
be given clinically. Alcoholism and diabetes, feverish 
sweating and stress all lower zinc levels. Severe 
deficiency causes hair loss, moist eczema of the mouth 
area, impotence, apathy, diarrhoea. 

33. Arsenic (As) sometimes seems to be needed by 
horses, and is included also in chicken pellets, but is a 
poison to animals even at slight concentrations. 
Polluting sources come often from gold processing 
areas, or from chickens fed on pelleted foods 
containing high arsenic levels. 

34. Selenium (Se) deficiency in lambs causes "white 
muscle" or "still lamb" disease which is cured by 
selenium and vitamin E injection. It also causes “illthrift" 
in animals in many countries where a severe dietary 
deficiency occurs. Five mg/year is sufficient for sheep; 
more can cause toxicity. Seaweeds may supply 
sufficient selenium to gardens. 

38. Strontium (Sr) is becoming, as a long-term and 
very poisonous radioactive element (Sr90), a 
widespread danger from atomic plants. It now pollutes 
many areas, milk, and is being used as a "blackmail", 
e.g. in New York water supply in 1985. One of the great 
pollutants of the future, it causes cancer at absorption 
site, leucaemia in children, and is a "hidden cost" (very 
hidden) of the atomic age. It is excreted in urine of 
breast-fed babies, and concentrates 4-8 times in 
cows' milk, thus levels in cows' milk must be monitored 
after atomic fallout. There are no safe levels. Ordinary 
strontium is a trace element. 

42. Molybdenum (Mo) is a trace element for clover 
establishment, and needed by all plants, rhizobia. A 
few ounces per acre is used on many acid soils, and 
rarely again needed. It is locked up not by alkali or lime 
but by sulphuric acid, and may therefore be deficient in 
plants subject to acid rain. Legumes need molydenum 
for nodulation, but non-legumes deficient in 
molybdenum can concentrate dangerous levels of 
nitrates, causing “leaf burn". 

48. Cadmium (Cd) is a poison that is concentrated 
by green leafy plants and shellfish. It is derived from 
traffic (tyres) and superphosphate. It may already be in 
very high levels in acid soils of market gardens using 
artificials (as it is in Canberra). Cadmium causes 
painful human disease ilai-itai (Japan) and permanent 

50. Tin (Sn). Ores and wastes create plant 


establishment problems. It is not noted as toxic at low 
levels in diets, but can become toxic at high levels in 
canned food. 

51. Antimony (Sb) As lor arsenic. 

53. Iodine (I). Deficiencies occur in weathered 
basalts, causing growth problems and goitre; these are 
remedied by fish and shellfish, seaweed diet. Ii3i now 
a common radioactive fall-out from atomic plants and 
tests; it poisons milk over wide areas, and affects 
thyroid function. Iodine can cause cancer, death of 
children from hyperthyroidosis; a real risk from atomic 
establishment and tests. 

80. Mercury (Hg) is a common poison released by 
mines, metal processes, acid rain, and is more active 
in organically polluted areas. It creates very serious 
coordination and sanity problems, central nervous 
system malfunction, bone deformity, insanity. 

81. Thallium (Tl) is a toxin, causing birth deformi- 

(...from page 1881 

(soaking), or by being pressured upwards by an 
aquifer flow in permeable sediments. 

• Water travels by throughflow, traveling by the 
effects of gravity downslope in the profile. 

This latter effect produces soil types called catenas 
specific to slope, drainage, rock type, and landscape 
(Figure 8.3). 

INFILTRATION effects are most marked in soils 
where, for very long periods, a succession of light 
intensity rains have alternately wetted and then dried 
out in the soil. At the wet-dry boundary we find 
concentrations of easily soluble salts and deposits of 
minerals and nutrients (sometimes in over-supply). 

The second set of effects on element transport are 
biological. Elements are actively sought out or selected, 
and either concentrated or dispersed by living 
organisms. These effects are myriad in total, but some 
of the ways this is known to happen are: 

fungi, bacteria, and invertebrates which can seek out, 
assemble, and change specific compounds to stable 
new forms as concretions or nodules. Iron, 
iron-manganese, calcium, phosphate, zinc, nickel, 
copper, selenium, cadmium, phosphate and nitrogen 
are all so selected and concentrated by one or other 
form of mycorrhiza (root fungi), bacteria, molluscs, or 

DETRITUS. Diatoms, swamp peats, whole forests, 
sponges (and their spicules of silica), molluscs, and 
vertebrates are at times buried by vulcanism, 
sedimentation, or deposition in oceanic deeps to form 
specifically concentrated sediments, and eventually ore 
bodies or rock types (coal, rare earths, or manganese 

plants seem to be able to dissociate and transpire a 
great variety of substances to atmosphere. Reeds do 

ties, thus very dangerous. 

82. Lead (Pb) is a common poison from petrol, old 
paints, battery burning. It is a serious urban soil 
pollutant, needing heavy organic soils to block uptake, 
or removal of lead-concentrating vegetation for 
disposal. Earthworms may concentrate lead to lethal 
levels in polluted soils. 

86. Radon (Rn) is a gas from the decay of uranium. 
Seeps up in most soils, especially over volcanic areas, 
igneous rock, and can pollute super-insulated 
buildings if the air is not exchanged. Several million 
homes in the UK and USA have high levels of radon. 
Avoid building poorly ventilated homes in areas of 
radioactive ores, granites, and basalts, or the use of 
such rocks or crushed metals in buildings. If houses 
are to be super-insulated or draught-proofed, then 
adequate heat exchangers must be fitted to bring in 
clean air. 

this with mercury, hydrogen, and other elements from 
phosphates to chlorine. Not all of these are vapourised 
to drift off in the winds; many are deposited in special 
leaf repositories, or evaporated to a wax, dust, or 
efflorescence on the leaves and stems of trees, from 
where they are washed down again to earth by rain 
throughfall. In this way, both major plant nutrients and 
minor elements are concentrated in the top 4 cm (1-2 
inches) of soil below trees. Metals, oxides, halogens, 
acids, alkalis and salts are also concentrated. 

CESSES. We build our bodies up by ingesting a large 
range of complex foods, as do all living things. From 
these ingested bodies, materials are selected to build 
our bones, flesh, blood, and brain tissue or organs, 
nails and hair, fats and milk. Thus, our own bodies and 
those of other animals are complex storages of 
elements; even our faeces package very different 
concentrations of potash, nitrates, and pollutants from 
the different concentrations of foods that we eat. And, 
by our behaviours, these are variously disposed of in a 
personalised, culturally-determined, or species- 
specific way in the environment. Plants and animals 
ceaselessly ingest and defecate, refect and exude over 
their whole lifetimes, thus altering the concentration of 
nutrients in their immediate environment. 

_ 8 I 8 _ 


Of the parent rocks of soils, we speak of ACID rocks as 
containing 64% or more of silica (Si02>, 
INTERMEDIATE rocks at 50-64%, BASIC at 40-50%, 
and ULTRABASIC at less than 40% silica. Of soils 
themselves, we speak of acidity and alkalinity in terms 
of a logarithmic scale, in which each point is 10 times 
the concentration of hydrogen ions less than the scale 
point below it, so that pH 8 (alkaline) is 10 x 10 x 10 x 
10 or 10,000 times less acidic than pH 4, and pH 3 ten 


times more acidic than pH 4. 

Table 8.3 serves to portray the availability to plants 
of some important elements with respect to pH value. 

We commonly speak of "hard" (alkaline) or "soft" 
(acid) waters. The latter used with soap lathers easily, 
and is desirable for washing; the former (including 
seawater or other alkaline waters) is difficult to use for 
washing, as soaps and detergents are themselves 
alkaline and so do not easily dissolve in other alkalis. 

Soaps, based on sodium or potassium (ash) and fats 
will lather in soft acidic waters, and detergents based 
on phosphates or sulphur, lather in hard waters. Hard 
waters contain calcium (Ca*) or magnesium (Mg*) ions. 
Soft water contains hydrogen (H*) ions. 

The properties of alkali (soaps or carbonates) and 
acids (vinegar, citrus juice) have long been recognised 
and used medicinally or in village chemistry. The word 
for deserts in Arabic is al khali ("the salt"). 

Acids and alkalis arise from the solution of oxides, 
hydroxides, sulphates, or carbonates of metals and 
non-metals. In water and soil water, the common rock 

TABLE 8.2 




(Compost generally, rock 

by crop 

in Soil 


in soil 






Legumes, water plants, 

Basic to crop growth. 






Ash. leafy materials, kainite. 
bone meal. 

Basic to crop growth 






Bones, bird manures. 

Found in super¬ 
phosphate (acid-treated 
bone or rock phosphate 

Basic to crop growth 






Elemental Sulphur. 

Volcanic mineral deposits, 

Adjusts pH towards acid. 






Limestone, some crops 
(e.g. buckwheat), dolomite. 

Adjusts pH toward alkaline. 











(Seaweed concentrate gen¬ 
erally. sea algae) 



(All of these are needed in 
minute amounts, and either 

Likely to be deficient (with 
Mg) at high pH. 






made available by adjusting 
pH or by adding oxides, sul- 

Likely to be deficient in 






phates, or sodium salts of 
the element itself. Most are 

Likely to be deficient in 
coastal plain pastures. 






present im seaweeds, or 

Frequently deficient. 


0 002-1.0 




seaweed concentrate.) 

Frequently deficient. 






Deficient in deep, volcanics. 







MULCH OR COMPOST OF MIXED MATERIALS SUPPLY ALL NUTRIENTS, plus if available. 200g dry pulverized poultry manure per 
square metre. Gross deficiencies are likely to occur in the primary nutrients; calcium and phosphates are usually low in old or 
leached or overworked soils. Rock dusts add potash, limestone adds calcium, dolomite for magnesium, and tree or clover legumes 
for nitrogen. Manures add most of these except calcium. 

N:P:K is ideally added in a 5:8:4 ratio, for sandy loams with 5 parts of lime to balance acidity. In a 5:6:6 ratio for clays. 

Fertilizer can be added as manure teas sprayed on leaves, with seaweed concentrate, and in humid weather this is absorbed in from 
24-56 hours. 


and soil constituents are: 

• Metals: Sodium, potassium, magnesium, calcium, 
and minerals (iron, zinc, aluminium, copper). 

• Non-metals: Silicon, sulphur, traces of phos¬ 
phorus, boron, fluorine, chlorides. Carbon is also found 
in organic soils. 

In solution, metals release positive (H) ions. 
Nonmetals release negative (OH) ions. Chalk, 
limestone, calcite, dolomite, magnesite, and gypsum 
are rocks and minerals giving rise to hard water (from 

air and water which gives carbonic acid). All of these 
are carbonates, sulphates, or oxides of calcium or 
magnesium, or both, e.g. dolomite. 

All these below are used to raise pH values in soils: 

• CHALK and LIMESTONE are calcium carbon¬ 

• GYPSUM - calcium sulphate. 

• MAGNESITE - magnesium carbonate 

• DOLOMITE - calcium magnesium carbonate 

In the table of elements (Centrefold), groups I and 11 

TABLE 8.4 






n <. . » 





Add magnesium-sulphate as spray at 10 g/L, 

Add Dolomite (for Ca. Mg) at 100-300 g/m 2 

or at 45 g/m 2 - 

(Neutralise with lime 20g/m 2 ) 


Add ammonium sulohate or fine dolomite 

Add water-retaining polymers, add gypsum. 

(for Ca). 


Add zinc every 7 years at 1 g/m 2 

Use copper-based sprays sparingly. 

Add water-retaining polmers. 

Add neutralised superphQSPiiate (lor P). 


Add 10 g/m2 bentonite or monmorillinite 

Add bentonite, polymers. 

clays, polymers. 


Add ferrous sulphate (for Fe) at 23 a/L as 

Add dolomite, gypsum, polymers. 

a foliar spray. Add polymers. 


Trial Cobalt sulphate at 0.11 g/m2 or foliar 

Add potash Trial neutralised cobalt. 

sprays of cobalt. 

Wet areas 

Use rock phosphate, dolomite 


Add copper sulphate (for Cu) every 7-14 

Add neutralised copper sulphate (for Cu) 

years, if cropped, at 1 g/m 2 . 

every 7-14 years, if cropped, at 1 g/m2. 

Add zinc sulphate (for Zn) every 7-14 years 

Do not add sulphur unless absent. 

at 1 g/m2. 

Add Zinc sulphate 2:1 with lime at 1 g/m2 

every 7-14 years. 



Add Silicate or spray silica solutions. 

Coarse textures in tropics. Add cement. 

(Calcium silicate) at 100-400 g/m 2 . 


Add dolomite, gypsum. 


Add polash if cropped. Add zinc_sulphate 

Addootash if cropped. 


Add copper sulphate 1 g/m2 every 7-14 

Add neutralised copper sulphate every 7-14 


years at 1 g/m 2 


Acidify with silliilM. add manganese 

Add gypsum to improve drainage, reduce 

sulphaie. at 2-3-g/L as spray. 

salinity in dry areas. 

Molybdenum needs trials at 350 g/ha. 


Iron oxides 

Add copper sulphate at 1 g/m2. 


Immobilize phosphates. 


Blood and bone, manures, compost, acidic 

Blood and bone, manures, compost, 

phosphate, urine for potash. Foliar sprays 

dolomite, seaweed, pebble dust from 

of seaweed concentrate. 

cement works 


contain the non-metals of which lithium, sodium, 
potassium, magnesium, calcium, strontium, and 
barium compounds give up alkaline (OH) ions to soils. 

The usual soluble (solid) bases for alkalis are 
magnesium, calcium, potassium, barium, sodium, and 
selenium. The usual soluble (liquid or gaseous) 
compounds for acids are silica and sulphur based, or 
derived from humus. 

The measurement of acidity-alkalinity (pH or 
hydrogen ion concentration) is basic to soil and water 
science, as it affects the availability (solubility) of other 
key or trace nutrients, and (at its extremes) the ability 
of life forms to obtain nutrition, or even to live. 

The pH scale ranges from 0 (acid) to 14 (alkaline), 
although in nature we rarely find readings below 1.9 
(lime juice) or above 11.0 (alkali flats). In the presence 
of air, and in ploughed and aerated soils, both metals 
and non-metals form oxides, and these dissolve in 
water or soil water. 

The METALLIC OXIDES (bases) form alkaline 
solutions. The litmus reaction is blue. There is an excess 
of hydroxide ions (OH ) present in solution. 

The NON-METALLIC OXIDES form acidic 
solutions. The litmus reaction is red. Excess hydrogen 
ions (H*) are present in solution. 

Common acidic substances are citrus juices and 
batten' acid Common alkaline substances are sodium 
bicarbonate (baking soda) and washing soda. 

As rain falls, carbon dioxide in the air combines with 
water to form weak carbonic acid (as in soft drinks); 
this helps to dissolve metallic oxides in soils, and to 
bring the minerals of rocks and soils into solution. 
Sulphur from industrial processing, or from pyrites in 
rocks or soil can form sulphuric acids, and these also 
aid the solubility of metallic oxides. Phosphorus and 
nitrogen can form phosphoric and nitric acids with 
water. Silica in soils dissolves to silicic acids, and 
chlorine to hydrochloric acid. Weak nitric acid is a 
plant growth stimulant (New Scientist 22 May 86). All 
of these acids, in moderation, are helpful in nutrient 
supply to plants. 

pi I is not a constant for soil or water. Not only does 
it exhibit diurnal or seasonal changes due to rain, 
growth, and temperature changes, but it is essentially a 
mosaic in soil crumb structure, on the surface of 
colloids, and at microsites. Further, pH exhibits vertical 
soil gradients, being more acid in surface mulches and 
more basic or alkaline where evaporation, wormcasts, 
and capillary action draw up bases to the surface of the 
soils (dry or wet-dry areas). Mosaics on a larger scale 
are imposed by slope, and both rock and vegetative 
types. As long as people are aware of this, and realise 
that root hairs can both create and seek out ideal pH 
environments if there are no gross imbalances, then 
gardens are likely to contain every sort of pH level 
somewhere in the soil. 

Only by grinding mixed samples of soils to damp 
pastes, or measuring conductivity, can we "average" 
pH and obtain some idea of net balance, but (as usual) 
our measuring methods alter the thing we measure. If 

A 2KS2T 

4 o *5 *o g S bo t>S 1o IS do 6S lo 15 too 

4 - 5 5 6 * S 1 75 OB-5 * is lO 



A In inorganic (mineral) soils. The widest parts of the black areas 
indicate maximum availability of each element The curves represent 
pH values 

[After Nelson. L. B . (Ed.). Changing patterns ot fertiliser use. Soil 
Science America. Madison. Wl (1968)| 

B In organic soils The widest parts of the black areas indicate 
maximum availability of each element 
[Alter Lucas. R E.. amd J. F Davis. 'Relationships between pH values 
of organic sols and availability of 12 plant nutrients'. Soil Science. 

92 17-182 (1961)| 


we keep the average pH value to between 4.5 and 10, 
we can grow a wide range of plants and rear aquatic 
organisms if calcium is present. If we narrow the range 
to pH 6.0-7.5, most vegetables grow well in gardens. 
Outside these ranges (less than pH 4.0 or more than 
pHlO.O), only specialised bacteria or higher organisms 
can cope. Moreover, soil humus is itself a buffer as is 
calcium (lime); humus will grow plants at satisfactory 
levels even if the pH changes, so that limed and 
mulched gardens rarely show plant deficiency 

_8 I 9_ 


We think of soils as mineral compounds, but the pie 
diagram in Table 8.4 will alter that impression; it does 
not, of course, represent any one soil, but is an average 
sort of figure for a good loam with adequate humus. 
Outside the pie, I have noted some of the possible 
ranges of variation from peats to sands in old dunes. 

Soils in nature can vary from a humus content of 2% to 
close to 1007, (as peats). In gardens, 40% or more 
humus helps block heavy metal uptake by plants, 
holding heavy metals bound in colloids. Many 
compost-fed or mulched garden soils contain 10-30% 
humus (some much more). The effect of adequate soil 
humus is both physical, in effecting good water 
retention and in preventing erosion, and chemical via 
colloid formation. The breakdown products of humus, 
including the mineral content of the donor plants, form 
the readily-available and biologically active 
components of soil that are of value to newly- 
established plants. If these plants are perennial or (in 
part) mulch-producing, and if we return food wastes 
to the garden (including urine and well-composted 
faeces) then very little humus loss occurs. 

On the broad scale, humus can only be provided by 
the root and the above-ground mass of grasses, trees, 
and plants. Prairie grasses and broadleaf trees are 
particularly effective at this job. When we aerate 
(plough) soils we turn up humus and oxidise it to 
carbon dioxide, thence to atmosphere. It is lost. 
Burning the vegetation is worse, with a host of 
additional pollutants (terpenes, creosotes, nitrogen, 
and dust particles), and a rapid loss of soil humus. 
Where soils are not tilled or burned, soil humus lasts a 
long time (hundreds or even thousands of years) and 
provides for a complex soil life. 


Mulching is here defined as covering the soil surface 
with 15 cm or more of organic material, as a loose 
(uncompacted) mulch; 8 cm of tight-rolled sawdust 

does not qualify! Mulching is more generally applied 
to loose dust "mulches", plastic sheet mulches, and so 
on, and these may have specific local value in soil 
amendment, heating, sterilisation, weed suppression, 
or pest reduction, but as here considered, the object of 
mulching is to add plant nutrients, buffer soil 
temperatures, prevent erosion, promote soil life, and 
restore soil structure. 

Plastic mulches, soil gels (polyacrylamides), 
herbicide-treated soils, and organic or natural mulches 
may all achieve the result of preventing erosion and 
helping soil crumb structure develop. Only long 
periods of natural mulches stabilise nutrient supply, 
and complex the soil life. None can be judged over one 
or two seasons, as it can take 3-5 years to create a 
balanced soil under mulch from a compacted or 
mined-out soil. Even longer periods are necessary to 
develop humus in permanent crops assessed for yield 
on the broad scale, where added mulch is not carried to 
the site, but derived from tree wastes and 
specially-sown crop (green manures) produced on the 
site itself. 

Used in areas such as wet tropics and arid lands, or 
on dry coarse sands, mulches may prove to be 
ephemeral (even if their effects continue), as ants, 
termites, and leaching reduce the mulch to humic acids 
or underground storages in fungi and bacteria. In 
particular, water absorption is improved under mulch, 
both as field crop mulch and imported garden mulch, 
thus water needs are reduced. Jeanette Conacher, in 
Western Australia's Organic Gardening , 1979, reporting 
on extension trials in Nigeria, records 11% better water 
infiltration on low- to no-tillage and mulched plots. 
Under mulch, excessive soil temperature ranges are 
buffered, being cooler by day and warmer at night or 
in winter. Seed germination is enhanced, and over the 
long term, major nutrients (N, P. K) remain at 
satisfactory levels. Only under mulch does the 
population of important soil organisms, such as 
earthworms, increase. 

Mulches need some selection for minimal weed seed, 
minimal residual biocides, and for best effect on 
specific crops (tested as row-by-row comparisons). 

Plastic mulches (black for heat and weed control, 
silver for aphid repellancy) have a more limited role, 
important in the short-term, but often expensive or 
impractical in poor countries, or rejected by growers 
who suspect that many plastics release persistent 
chemical polymers of unknown effect on the soil life. 

Mulch is an excellent way to add nutrients to soils; 
the "cool" decay loses little nitrogen, while stimu¬ 
lating soil life generally. There are some problems with 
compost, where "hot" (aerobic) heaps heat up and 
nitrogen (ammonia) losses are severe. Cold heaps 
(pitted or silage) do not lose nitrogen, but neither do 
they kill weed seeds. One percent of superphosphate 
added to a hot compost heap prevents ammonia 
escape. Chinese scientists get the best of both worlds 
by first building an aerated heap with bamboo poles as 
holes to create air tunnels. This is then covered with 


mud and the heap heats up to 55-60°C (130-140°F) for 
a few days. Then all holes are sealed, and the rest of the 
decay is anaerobic. With sealed boxes, either hot or 
cold processes can take place. 

Compost or mulch is critical to preserving soil crumb 
structure, buffering pH, and (in taste tests) improving 
sugar content and the flavour of vegetable product. 
The gums and gels produced by soil organisms create 
crumb structure, aerate the soil, and darken it so that it 
heats up faster in spring. The humic acids assist root 

development dramatically even at levels of 60 ppm 
carbon. Inorganic (chemical) and mechanical farming 
can as easily destroy soil structure. 

In the U. K. (N«t> Scientist 3 Nov. '79), liquid manures 
sprinkled on straw in silos or tanks, together with a 
forced air draught, produce compost in about a week 
(efficient open piles encased in straw need 10 days). 
The liquid effluent system plus straw- is suited to 
treatment of a manurial sludge (still full of seeds) such 
as that we get from biogas digesters. It is best to use 


_ &10 _ 


this with dry twiggy or straw material as hot compost 
to both kill weed seeds and to produce useful heat, 
after the compost pile has been made. However, in 
severe winter areas, such “efficiency" is 
counter-productive as a slower heat release from large 
compost piles of 10-50 cubic metres (12-59 cubic yards) 
can provide heat over a long period in winter and 
greatly reduce glasshouse and house heating costs, 
while the compost itself is best applied to soil in 

Even using organic residues, or "natural" wastes, soil 
problems can arise from a concentration of nitrates in 
manures, or toxic mineral residues. Leaf material cut 
and mulched (or composted) green will contain more 
nutrients than fallen leaves, although the latter are still 
useful for humus production. Kevin Handreck 
(Organic Growing, Autumn '87, Australia) has 
identified potential mineral contamination from these 

• Galvanized, copper, or brass containers containing 
wet residues of manures, or manurial teas; clay, 
stainless steel, glass, or iron are preferable. Zinc and 
copper are produced in excess from galvanized or 
copper/brass containers. 

• Manures from pigs, poultry, cattle, or sewage 
sludges can add excessive copper, zinc, nickel, boron, 
lead, or cadmium to soils (and especially acid sandy 

Where such elements are naturally deficient, such 
manures may initially help, but heavy or constant 
application will build up a toxic soil condition. Excess 
zinc can be built up by using earthworm casts from 
contaminated pig, sheep, or domestic wastes. Animals 
penned in galvanized areas can produce excess zinc in 
pen wastes. 

It is in poultry mixes that such contaminants show 
up, with excess zinc inhibiting plant growth and 
health, so that the urban gardener should test and use 
safe mixes, or proceed via plant trials. Handreck 
recommends a limit of 10 % worm casts in a potting 
mix. In such cases, nitrogen and potash can be 
supplied by dilute urine. 

Note that copper, arsenic, and other minerals are 
commonly added to stock feeds, and therefore try to 
buy clean natural feeds from organic sources. After 
initial soil treatment, and a continuing watch for 
foliage deficiency symptoms (see Deficiency Key, this 
chapter), the safest course is to grow our own green 
manures as the foliage of leguminous hedgerow, 
windbreak, or intercrop, and to use these as mulch and 
compost materials. 

The structure of soil (whether compact or open) 
depends on the soil composition itself, the way we use 
it, and the presence or absence of key flocculating or 
ionic substances (synthetic or natural). Crumb 
structure in well-structured soils permit good gaseous 
exchange and free root water penetration without the 
creation of excessive anaerobic conditions by 
waterlogging. In free sands, and in the kraznozems 
developed over deeply-weathered basalts, crumb 
structure is either not a factor, or else is so well 
developed that it permits leaching (to immobile clay 
sites) of almost all applied fertilisers. 

However, in most other soils, we would like to see a 
good crumb structure develop as in our gardens or 
crop soils. Where crumb structure is poor, we can use a 
great variety of coulter and rip-tine machines, soil 
additives, and deep-rooting plants such as trees or 
lucerne to re-open and keep open the soil structure, 
which in turn allows adequate water penetration and 
drainage, and eventually develops the oxygen- 
ethylene processes that make bound nutrients 

Soil crumbs of 0.2-2 mm diameter can form as little 
as 10% of the total soil volume, and still produce crop; 
below this, crop is greatly reduced and impoverished. 
The same soils can, when not ploughed lifeless, contain 
92-95% of such crumbs (Leeper, 1982). We destroy 
crumb structure by destroying permanent vegetation, 
flooding soils for long periods, using high-speed or 
heavy vehicle cultivation, stocking with sheep or cattle 
in especially wet periods, using fertilisers that 
deflocculate the soils (e.g. too much potassium where 
soil sodium levels are already high), or by burning in 
hot periods. 

The whole set of disasters outlined above can 
collapse soils to the cemented, dusty, hydrophobic, 
salted and desertified areas typical of wheatlands on 
desert borders. It is a question of improper use, 
disastrous planning (or no planning), and a total lack 
of applied goodwill to earth. 

Given a good structure, pores develop for the 
diffusion of gases and exchange of ions, provided that 
we make the transition to perennial, low cultivation 
systems of forest and crop. 


Colloids are stable aqueous gels or suspensions of clay, 
organic, or long-chain polymer particles in a finely- 
diffused aqueous state in soils. These arc particles so 
fine that they stay in suspension unaffected by gravity, 
and become active sites for ionic bonding and 
interchange. Colloids also form gels which hold soil 
water reserves, and are in part formed by or derived 
from natural (and more recently, artificial) substances 
some of which form hydroscopic gels by water 


TABLE 8.5 




Noxious? V-i Noxious? 
\ /Y Y\ / 




N / \ Y 

—< SOLIDS? V— 

(c) SPRAY 








ulch directly on soil |Use as manures on (Spread on soils of (Drill below soil 

surface at >12 cm 

Least effort for best 
results in gardens. 
Controls weeds, 
lessens labour. 


intensive plots and 

Energy used but good seed beds, 
results obtained. Most effort and most 
nutrient (ammonia) 
loss, but effective for 
specific materials. 
Energy yields as 
biogas, heat. 


Good results, no 

pray as liquid on 
fields, foliage, or use 
in aquatic systems. 
Little effort for good 

Energy yields as 


(a) Nut husks and shells; coffee, teas, and cocoa resi¬ 
dues; shredded paper and branches; bark, woodchips. 
and sawdust; and old carpets, underfelt (no/ pesticide 
treated ones), bags, canvas [all made of natural 

(b) Hay with seed heads, weeds in flower, bulbils or 
roots of weeds. 

(c) Sewage and sullage. liquid manure and urine, meat 

and animal paunches and trimmings, general household 
wastes. Add lime and superphosphate ( 1 %) to hot 
compost; ‘teas' of seaweed and manure. 

(d) Sludge from digesters and weed-free manures. 

(e) Chicken and bird manures, litter from animal sheds, 
blood, bone, feathers, hide scraps, seaweeds. 

(f) Dissolved minerals, urine, seaweed and manure 


TABLE 8.6 


(After McDonald etal] 

Fine clay 

< 0.002 

Clay particles 



0.002 - 0.02 


0.02 - 2.0 


0.02 - 0.2 


0 .2-2 








20 - 60 


60 - 200 


200 - 600 





Humus or humic decay and bacterial products provide 
colloids, as do finely ground graphite and silica, fine 
clays (particles of 2-200 millimicrons) such as illites, 
bentonite (usually deposited on clay pans from 
evaporation of clays in suspension), grain flours and 
animal (gelatinous) flours, e.g. from hooves, horns, 
sinew wastes, albumen and so on. Bacteria also secrete 
polysaccharides which form soil gels. 


Soil conditioners which form stable colloids are sold 
under a variety of trade names (ask a local agricultural 
supplier), e.g. Agrosoke®, Ikedagel®, Terrasorb®, 
which are hydrophilic (attract water) as are many 
natural gels from grain products and seaweed. Water 
conservation of up to 50% is claimed for some of these 
additives. Most artificial gels are acrylic-based 
(acrylamid polymers) and supplied as granules able to 
absorb hundreds of times their weight in water. They 
are used to great effect in nursery plants, row crops, 
new tree plantings in deserts, and in transplanting. The 
acrylics are applied to soils at 6 kg/ha or more, and 
conserve irrigation water by preventing evaporation 
(Small Farmer, New Zealand, Aug. '84). These 
substances are of value in seed pelleting. 

Colloids also form hydrophobic (repel water) 
substances such as those of clays and some soil fungi 
products. The surfaces of colloid particles are usually 
negatively charged, as are root hairs, and thus attract 
positive ions to their surfaces, e.g. the positive ions of 
sulphates, nitrates, and of metals (sodium, calcium, 
magnesium, iron). About 99% of such ions are so held 
in soils (Leeper, 1982). Colloids from humus are 
hundreds of times more effective than clay colloids in 
ion exchange in soils. 

Ammonia and sodium can dislodge these ions, and 

they can become available to plant roots, which attract 
them by producing negative (H) charges. With too 
much flushing by sodium, the calcium and metallic 
ions can be lost to leaching processes and carried to 
streams, hence to seas or lakes. 

Colloids used in water softening capture calcium 
ions and release sodium ions, allowing soaps to lather. 
Ferric oxide colloids have positive charges and give 
water a brown stain, typical of waters issuing from 
acid peats and pine forests. The colloid particles can be 
flocculated (aggregated) and settle out if aluminium 
salts (sulphates) are added; and this may happen as a 
result of acid rain, or can be induced with the acid 
forms of any negative particles. Salt also flocculates 
colloids up to the point where excess sodium 
deflocculates clays, with calcium and other ions, which 
is the effect of high salt concentrations in dryland soils 
(over 1-5 ppm salt). 

Burning destroys the colloidal properties of surface 
clays, and is another reason why desert soils leach out 
after fires. Burnt clay particles no longer form colloids, 
and become poor in mineral nutrients, which are then 
found only in deep soil profiles. Organic humus forms 
black slimy pools on top of the collapsed soils. 

It is the clay particles and colloids (organic and 
inorganic colloids) that bind water and nutrient in 
soils. In the tropics at least, most of these colloids are in 
the biomass of the soil as cellular gels, or are produced 
as sheathing material by soil bacteria. Without colloids, 
soil minerals rapidly leach out and become poor in 
nutrient. Fire, clearing, ploughing, and cultivation 
destroy such colloids and soil structure, as does excess 
sodium ions. Thus, to hold and exchange nutrients, we 
as gardeners need to develop natural or artificial 
colloid content in soils, from where plant roots and soil 
fauna or flora derive their water and essential 
nutrients. Very little clay is needed in sandy gardens to 
create a colloidal soil environment, and life forms are 
encouraged and developed by humus, mulch, and 
perennial plant crops. Good soil structure (to hold the 
colloids) is developed by careful earth husbandry, 
together with flocculating additives such as gypsum 
and humus. 


The water content of soils is a soup of free-living 
organisms, dissolved gases and salts, minerals, gels, 
and the wash-off from throughfall in trees (waxes, 
frass, tree "body wastes"). Organic and inorganic 
particles are held in soil water. Soils have a widely 
variable water-holding capacity dependent on their 
composition and structure, so that sands absorb and 
retain water more quickly than clays, but clays hold 
more water per unit volume. Available water thus 
varies from 2% (surface sands) to 40% or more of soil 
volume. We can assist the quantity held in dry sites by 
swaling, contouring or terracing, loosening soils, 
adding flocculants, introducing artificial or natural gels 
(seaweeds or plastic absorbers), or by placing a clay or 


plastic sheet layer 30 cm below the surface of gardens. 

In soils that become waterlogged, we can resort to 
raised beds or deep drains to reduce infiltrated water 
build-up, or plant trees to keep active transpiration 
going and so reduce soil water tables and re-humidify 
the air. 

Two factors at least affect soil water availability: 

• The strength of molecular bonding of water to 
particles in the soil (ionic bonds). Plant root hairs 
cannot remove this bound-water at pressures above 15 

• The salt content of the water. Too many salts, and 
the soil water exerts reverse osmotic pressures on plant 
roots, and will take water from the roots. 



Soils are permeated, where not waterlogged, by the 
gaseous components of the atmosphere (80% nitrogren, 
18% oxygen). This enters the soil via pore spaces, 
cracks, and animal burrows, and diffuses via pore 
spaces to plant roots. The exchange of gases, atmo¬ 
sphere to soil and soil to atmosphere—the breathing of 
earth—is achieved by a set of physical and biological 
processes, some of which are: 

• EARTH TIDES. The moon tides, much subdued on 
continental masses, nevertheless affect groundwaters 
in cobbles or boulders, the earth itself (about 25 cm rise 
and fall across the continental USA), and of course the 
soils of estuaries and mud flats (where air can be seen 
bubbling up for hours as the tide rises). 

Everywhere, low or high pressure cells and turbulent 
wind flow creates air pressure differentials that draw 
out or inject air via crevices and fissures, or burrows. 
These same effects assist or retard the diffusion of 
water vapour across soil surfaces, and just as the wind 
dries out surface soils so it also, by fast flow, draws out 
other gases from soil. The gases of soil respiration 
(carbon dioxide), oxidation, aerobic and anaerobic 
metabolic processes, radon from radioactive decay, and 
simple or complex hydrocarbons from earth deposits 
or humus decay pass to air. 

Much of the ammonia and carbon dioxide in the 
atmosphere, and at least 16 % of the methane, is 
supplied by soil processes. 

• BIOLOGICAL EXCHANGE. A single large 
broadleaf tree, actively transpiring, may increase the 
area of transpiration of one acre of soil by a factor of 
forty; a forest may do so by hundreds of times. So 
oxygen, carbon dioxide, water vapour, metallic 
vapours, ammonia, and hydrogen or chlorine gases are 
transpired by algae, rushes, crops, trees, and herbs or 
grasses. Plant groups vary tremendously in the volume 
and composition of gases transpired. Although we owe 
much of our atmospheric oxygen to trees, a great many 
non-woody plant species consume more oxygen than 

they produce. 

Thus, the plant is a gaseous translator, trading both 
ways with air and soil. Some specifics of this trade are 
given in the section below on oxygen-ethylene 

Animals, too. are very active in opening up soils 
with small or large burrows; these act as pump pistons 
(like a train in a tunnel) to draw in and exhaust both 
their waste gases and atmospheric gaseous elements, 
which are then diffused to roots via soil pores. Many 
burrowers (ants, crabs, termites, prairie dogs, worms, 
land crayfish) raise up mounds or chimneys which 
then act as Pitot tubes for air flow or to create pressure 
differentials which draw air actively through their 
burrows. Or they erect large surface structures of 
permeable sediments across which waste gases diffuse 
(e.g. termite mounds). By a great many such devices, 
animals contrive to live in aerated or air-conditioned 
undergrounds, and increase gaseous exchange in the 

By way of titanium or rutile (TiFe), ammonia is 
manufactured in sands in the presence of sunlight. By 
way of ferrous iron, ethylene (C 4 H 4 ) is manufactured 
in anaerobic soil microsites. In anaerobic soils and 
waters, carbon dioxide, methane, sulphuretted 
hydrogen, ethylene, and sulphur dioxide are formed, 
and escape to air as biogas or marsh gas. The same 
products are present in the mottled soils of 
hydrophobic clays in winter, soils where crumb 
structure has been destroyed by misuse, where salt has 
deflocculated clays and caused soil collapse, or where 
water periodically floods the soil. Many of these gases 
are found as a result of humus decay and thiobacillus 
(sulphur bacteria) action. 

Ammonia is released from actively nodulating 
legumes (trees and herbs), and is used in unploughed 
soils as a plant nutrient. Thus, gaseous compounds are 
continually made in the soil itself by process of 
metabolic growth and decay in the presence of metallic 


catalysts and micro-organisms. Moybdenum, 
vanadium, and zinc all assist root bacteria in the 
creation of available soil nitrogen (as catalysts). 



Like pH, cation exchange, and structure, natural soil is 
always a mosaic of aerobic and anaerobic patches 
called micro-sites, where either oxygen (aerobic) or 
ethylene (anaerobic) sites develop. Ethylene inhibits (in 
the sense of suspending), microbial activity, and like 
carbon dioxide, is present as 1-2 ppm in soils (Smith 
1981). As the ethylene at an oxygen-exhausted site 
diffuses out, oxygen floods back and re-activates the 
site. Under natural forests and grasslands, this cycle, or 
dance, of oxygen-ethylene is continuous, and most 
nitrogen there occurs as ammonia, useful to plants and 
plant roots. 

When we cultivate and aerate, nitrogen becomes a 
nitrate or a nitrite (which then inhibit ethylene 
production), and ferric rather than ferrous iron forms, 
thus making ethylene formation difficult (the process 
from decaying leaf to ethylene production requires a 
ferrous iron catalyst). Also, plant nutrients are tightly 
bound to ferric iron and become unavailable for root 
uptake. It follows that the production of ethylene is 
essential to plant health and the availability of 

It is important to realise that the aerobic condition of 
soils such as we get from ploughing or digging not 
only creates a condition of "unavoidable" nutrients 
and ferric iron, but also oxidises humus, which goes to 
air as carbon dioxide. Also, most plant root pathogens 
require the aerobic condition. As well, the nitrate form 
of nitrogen, which is highly mobile, leaches out when 
bare soils (not plants) occupy the site. In all, ploughing 
and earth turning create a net loss of nutrients in 
several ways, thus atmospheric pollution, stream 
pollution, and low soil nutrient states. 

Smith (ibid.) therefore recommends least soil 
disturbance, the use of surface mulch (not 
incorporated) as an ethylene precursor (old leaves are 
best for this), and very small but frequent ammonia 
fertiliser, until soil balances are recovered. The ideal 
conditions would be: 

• Permanent pasture; 

• Forests; 

• Orchards with permanent green crop as mulch; 

• No-dig or mulched gardens; 

• No- or low-cultivation of field crop, or field crop 
between strips of forest to provide leaves and 
nutrients; and 

• The use of legumes in a similar proportion to that 
occurring in natural plant associations in the area, at all 
stages of the succession. 

Under these conditions, soil mineral availability is 
made possible and soils do not lock up nutrients in 
oxides or produce pollutants. 

When we achieve this balance, soil loss and mineral 
deficiency become yesterday's problems. And when 

plant leaf (not soil) deficiency can be adjusted with 
aqueous foliar sprays, nature then starts to function 
again to obtain nutrients from soils via microbes and 
root mycorrhiza at the microsite level. (Smith, A., 1981, 
"The Living Soil", Pemutculture Journal #7, July '81.) 

_ 802 _ 


On semi-arid and poor pasture, it is difficult to keep 
sheep at a stocking rate of 3-6/ha. The very same 
pasture may support 2-5 t of pasture grubs, or up to 
6.5 t of earthworms/ha , so that (like grasses) most of 
the animal biomass or yield is underground, out of 
sight. Even where wheat cropping is carried on 
continuously for 140 cycles (Rothhamsted, UK) the 
plough layer supports 0.5 t of living microbial biomass 
(New Scientist , 2 Dec '82). About 1.2 t/ha of organic 
carbon is returned annually to the soil as root and stalk 
material from grain crop. 

So large is the soil biomass that its growth must be 
very slow, sporadic, and based on a turnover of 
humus/food within the soil rather than a food input 
from the wheat crop wastes. Humus in this soil has a 
mean age of 1,400 years, and probably derives from 
forests that long preceded the wheat; it yields up its 
nutrients very slowly, and is resistant to bacterial 
attack. However, it is equally clear that there are 
periods of sudden food supply from root masses at 
harvest, and from root exudates during the growth of 
wheat (30% of plant energy may be lost as sugars or 
compounds released to the soil via roots). However the 
soil biota achieve it, they exist on a very meagre food 
supply for such a biomass, rather like an elephant 
eating a cabbage once a day! Of the total biomass at 
Rothhamsted, 50% is fungi, 20% is bacteria, 20% yeasts, 
algae, and protozoans, and only 10 % the larger fauna 
such as earthworms, nematodes, arthropods and 
mollusc fauna (the micro- and macro-fauna), and their 
larvae. Such classes of organisms are found in soils 
everywhere, in different proportions. Anderson (New 
Scientist, 6 Oct. '83) gives some idea of the complexity 
below ground, where every square metre of forest 
topsoil can contain a thousand species of animals, and 
1-2 km of fungal hvphae! 

Very small animals are able to live a basically aquatic 
life in soil, in the water film attached to soil crumbs, 
while larger species are confined to pore spaces and the 
burrows of macrofauna. 

A wheat field is not the place most likely to produce 
high levels of soil biota, and plough cropping has (in 
Canada) reduced humus levels to 1% of the original 
levels over much of the wheat country. 

Climatically, the balance and proportion of soil biota 
varies greatly, with the acid soils of coniferous and oak 
forest yielding few earthworms, and the humic peats 
even less, so that the soil recycled by worms also varies 
from 2-150 t/ha (0.5-25 cm depth of soil/year). 




[After Daniel L. Dindal) 


Energy llows m the direction of the arrows, lengths in millimetres. 1 

first level consumers. 2 = second level. 3 = third level. 

Ecological disturbance or imbalances by predation, 
aeration, disturbed soils, low oxygen levels, and 
compaction favour the bacteria over the fungi. Fungi 
are certainly more effective in wood or large plant 
material breakdown, and can transport materials not 
only from place to place (e.g. move nitrogen into 
decaying wood) but also move nutrient into higher 
plants via their intimate contact with the root cells of 
the host plant. Usually, such translocations are modest 
(a few metres), but occasionally a fungal species can 
send out many metres of hyphae to invade a tree, as a 
pathogen and decomposer. Thus, it pays higher plants 
to give energy to their fungal root associates as sugars, 
and to gain minerals or nutrients in return. 

Over time, the death of these soil organisms returns 
nutrient to new cycles. Even termite nests die out in 

20-30 years, and new colonies start up. Larger animals 
can have a profound effect on primary litter 
breakdown (millipedes, woodlice) and are typically 
plentiful in mulch, but rare in compost. As one can 
imagine, any accurate account of the relationship 
between such dynamic mass of species awaits decades 
of work, but some broad facts are emerging; for 
example, turnover of nitrogen by earthworms exceeds 
that of the litter fall of plants. Few species fall into 
clear-cut classes of food relationships, and the chain of 
events of predation, faecal production, and burrowing 
are further complications. 

As it is probably impossible to research at a 
species-specific level, and as the gross compart- 
mentalisation of ecosystem analysis is inappropriate, 
Anderson (ibid.) suggests a more possible study based 


on the interactions between the broad functional groups 
of organisms, or a size-food community. Here, he 
laments, "we know so little about so much." 

Large animals (earthworms to wombats) can create 
major changes in soils locally, by burrowing, soil 
turnover, faecal production from vegetation, waste 
products, and even alterations to forest successions 
after fire. In general, gross disturbances by colonies of 
larger fauna as in deserts (where rodent biomass can 
reach 1 , 000 - 10,000 kg/ha) shift the balance from soil 
fungi to bacteria. 

We can think of the soil biota as a reserve of other¬ 
wise easily leached nutrients (nitrogen, sulphur), both 
of which elements they gather, store, or concentrate. 
Their cycle of life and death, which in turn depends on 
soil temperature and season, releases small or large 
amounts of these essential elements at multiple 
microsites. Termites, in addition, may store calcium 
from subsoils in their mounds, and bacteria store a 
number of soil minerals. These are held in the mobile 
living reserves of the soil biota, and are released by 
their death for slow uptake by plant root associates. 
Many plant forms directly eat bacteria (algae in water, 
fungi) or insects and nematodes, so that plants are 
either direct predators of the soil fauna, or scavengers 
of the bodies of the soil organisms. 

A useful classification of soil biota based on size is as 
follows ( New Scientist, 6 Oct '83): 

1-100 millimicrons, e. g. bacteria, fungi, nematodes, 
protozoa, rotifers. 

• MESOFAUNA: Size range 100 millimicrons-2 mm, 
e.g. mites, springtails, small myriapods, enchytraeid 
worms, false scorpions, termites. 

• MACROFAUNA: Size range 2-20 mm, e. g. 
wood-lice, harvestman, amphipods, centipedes, 
millipedes, earthworms, beetles, spiders, slugs, snails, 
ants, large myriapods. 

• MEGAFAUNA: Size range 20 mm upwards, e. g. 
crickets, moles, rodents, wombats, rabbits, etc. 

In terms of sheer numbers per square metre, 

nematodes (120 million), mites ( 100 , 000 ), springtails 
(45,000), enchytraeid worms (20,000), and molluscs 
( 10 , 000 ) greatly out-number any other species in 
temperate grasslands. Fungi, however, may be 50% of 
the total living biomass. 

While the tradition of soil science has been to treat 
and analyse soils as mineral matter (the living 
component being carbonised or burnt off in analyses as 
"C" or humus content), the preoccupation of sound 
farmers, biodvnamic groups, mulch gardeners, and 
"no-dig" croppers has been the quantity and quality of 
soil life, both as indicators of soil health and as aerators 
and conditioners of soil. Another factor which deserves 
more treatment in science is the mass, distribution, 
migration, and function of roots and root associates, 
and the role of burrowers (not only earthworms, but 
larger mammals, reptiles, and a host of insects). 

The soil (if not sterilised, overworked, or sprayed 
into lifelessness) is a complex of mineral and active 

biological materials in process. No soil scientist myself, 
I rely on soil life and the health of plants to indicate 
problems. Diseases and pest irruptions can be the way 
we are alerted to such problems as over-grazing, 
erosion, and mineral deficiency. Removing the pest 
may not cure the underlying problem of susceptibility. 
Certainly, strong plants resist most normal levels of 
insect attack. 

Soil analysis, helpful though it is, can help us very 
little with soil processes. Until very recent years, we 
have underestimated the contribution of nitrogen by 
legumes or soil microfauna. In addition, the measures 
of soil carbon has rarely been related to the soil biota, 
whose lives and functions are not fully known. It 
seems curious that we know so much about sheep, so 
little about those animals which outweigh them per 
hectare by factors of ten or a hundred times, and that 
we do not investigate these matters far more seriously. 
Our most sustainable yields may be grubs or 
caterpillars rather than sheep; we can convert these 
invertebrates to use by feeding them to poultry or fish. 
We can't go wrong in encouraging a complex of life in 
soils, from roots and mycorrhiza to moles and 
earthworms, and in thinking of ways in which soil life 
assists us to produce crop, it itself becomes a crop. 


Worms have played a more Important part In 
the history of the world than most persons 
would at first suppose. In almost all humid 
countries they are extraordinarily numerous, 
and for their size possess great muscular 
power. In many parts of England a weight of 
more than ten tons (10.516 kg) of dry earth 
annually passes through their bodies and is 
brought to the surface on each acre of land; so 
that the whole superficial bed of vegetable 
mould passes through their bodies in the 
course of every few years... Thus the particles 
of earth, forming the superficial mould, are 
subjected to conditions eminently favourable 
for their decomposition and disintegration... 

The plough is one of the most ancient and 
most valuable of man's inventions: but long 
before he existed the land was in fact regularly 
ploughed, and still continues to be thus 
ploughed by earthworms. It may be doubted 
whether there arc many other animals which 
have played so Important a part in the history 
of the world, as have these lowly organized 

(Charles Darwin, The Formation of Vegetable 
Mould Through the Action of Worms, 1881) 

From the time of Darwin (and probably long before), 
copious worm life in soils has been taken as a healthy 
sign, and indeed more modern reviews have not 
reversed this belief (Satchell, 1984). Worms rapidly and 
efficiently recycle manure and leaves to the soil, keep 


soil structure open, and (sliding in their tunnels) act as 
an innumerable army of pistons pumping air in and 
out of the soils on a 24-hour cycle (more rapidly at 

Of themselves, they are a form of waste recycling 
product, with a dry-weight protein content of from 
55-71% built up from inedible plant wastes. Only a few 
peoples eat worms directly, but a host of vertebrates 
from moles to birds, foxes to fish depend largely on the 
worm population as a staple or stand-by food. 
Cultivated worms are most commonly used as an 
additive to the diets of livestock (fish, poultry, pigs). 

However, as processors of large quantities of plant 
wastes and soil particles, worms can also accumulate 
pollutants to extraordinarily high levels; DDT, lead, 
cadmium, and dioxins may be at levels in worms of 
from 14 or 20 times higher than the soil levels. Eaten in 
quantity by blackbirds or moles, the worms may 
become lethal. That is, if the "pests" that are moles, 
blackbirds, and small hawks abound on farms, there is 
at least some indication of soil health. Where these are 
absent, it is an ominous and obvious warning to us to 
check the soil itself for residual biocides. 

As non-scientists, most gardeners deprived of 
atomic ray spectrometers, a battery of reagents, and a 
few million research dollars must look to signs of 
health such as the birds, reptiles, worms, and plants of 
their garden-farm. For myself, in a truly natural 
garden 1 have come to expect to see, hear, and find 
evidence of abundant vertebrate life. This, and this 
alone, reassures me that invertebrates still thrive there. 

I know of many farms where neither birds nor worms 
exist; and 1 suspect that their products are dangerous to 
all life forms. 

All modem evidence agrees on the value of worms 
in fields, as decomposers and manure recyclers. They 
may be even more valuable as garbage disposal 
systems, and as fish or poultry food, providing a mass 
of high-protein food from vegetable wastes. 




Several types of concretion or cemented particles occur 
in soils. These are commonly the following: 

• CALCRETE ( caliche , platin, kunkar) is a hard, 
mainly level subsurface concretion about 0.5-1.0 m 
below a granular or sandy topsoil, typical of coral 
islands (calcium triphosphate), and the downwind 
areas of desert borders. Calcrete must be broken open 
to plant trees, or the roots will spread out laterally, 
allowing wind-throw to occur. On atolls, fresh-water 
deposits develop below the caliche. 

Broken caliche can be used as a building material 
and also forms a safe roof for tunnels or dugouts. 
Calcium/magnesium concretion, worsened by the 
addition of superphosphate, is whitish to creamy. In 

acid (vinegar), calcrete releases bubbles of carbon 

• SILCRETE ( cangagua ) is a grey to red shiny hard 
layer developed below some tropical forest soils, which 
gives a glassy surface if forests are cleared. The soil is 
concreted by silica deposits. If such deposits lie below 
forests, it is unwise to clear the forest itself. Durian : 
Silica-cemented non-wetting horizon, earthy, brittle, 
found only in volcanic areas. R ed-brown hardp an: 
occurs in many soil types, not volcanic, semi-arid, and 
is 10 cm-30 m (4 inches to 98 feet) thick. 

• FERRICRETE: Iron-cemented pans and soil layers 
of varying thickness, sometimes as thin sandy layers of 
5-10 mm; also alumina-iron laterites (often capping 
desert hills with veins of silcrete) or iron-manganese 
nodular horizons in soils. Ferricrete may lie over pale 
bauxites, and is also called ironstone, plinthite. Ortstein 
occurs in podzols as iron-organic hard B horizons, 
goffeer^k is a thick sandy coffee-coloured horizon, 
low in iron and easily broken; it is a common horizon 
in humic podzols. Duricrusts form hard silica-iron 
caps on hills in deserts. 

• PLOUGH PANS are usually clay-based com¬ 
pacted layers developed below croplands in wet 
periods; these can be caused by mouldboard ploughs. 

All of the above need ripping, explosive shattering, 
or deep mulch pits to establish trees. Sodium in soils 
may develop a "collapsed" cemented, greyish, gravelly 
pan (SOLCRETE) impermeable to water. Only 
deep-rooted trees, reduction of salt, and humus relieve 
these cemented conditions. Deep drainage of 1-2 m is 
essential for salted soils. 

Concreted soil layers (calcium or silica-cemented) 
are the calcretes ( caliche. platin) of dry islands and 
coasts, or the ferricretes (iron-cemented) of deserts. 
Any or all may form duricrusts (hard layers) in eroded 
areas. Under some tropical rainforest (e. g. in Ecuador), 
an iron-silica pan which follows hill contours, locally 
termed cangagua, lies 3 m below the forests; it is a 
daunting sight to see this glassy and impermeable 
surface after the removal of forest and a consequent 
loss of topsoil. Where cangagua is known to exist, 
perpetual forests used for products other than their 
wood (honey, fruits, medicines) are the only 
sustainable use of land. 

Some classes of very fine blackish sands, and sands 
invaded by hydrophobic soil fungi, are difficult to wet; 
the water sits on top as droplets. There are several 
remedies for this in gardens: 

• Ridge soil to make basins. 

Every square metre, core out sand and drop in a 
loam or clay-loam plug (4-10 cm by 30 cm deep). 

• Compost thoroughly and build up organic material 
to 8% of surface soil. 

• Add a handful of bentonite per square metre, or 
powdered clay from clay pans. 

• Mulch thoroughly, and plant. Keep surface mulch 



On the broad scale, deep ploughing in autumn (to 45 
cm) is used, followed by rotary plough or chopper, 
mixing of the top non-wetting profile of 10-20 cm (4-8 
inches) with subsoils. A cover crop is immediately 
sown to prevent erosion, and this used as a cover crop 
or green manure for deep-rooting crop or tree species. 
The successful establishment of trees permanently 
curbs the problem. 

CLAYS which seal on the surface in light rains are 
often sodium-rich and "melt" in rain. Remedies are: 

• Make low banks across run-off. 

• Add gypsum at 2-3 handfuls per square metre, 
and if possible flush out with fresh water (removing 
sodium as sulphate). 

• If practical, place sand over the surface to 4 cm 

For deep cracking clays and lumpy soils add a sand 
layer, scatter gypsum at a handful per square metre, 
and mulch. 

For acid or deep silica sands it is best to add clay and 
mulch, and to lay plastic at 0.5 m deep in garden beds 
(Figure 8.7). 



£\ A 



Plastic sheet prevents deep leaching . clays hold water at root level: 
mulch prevents surface evaporation. 



Figure 8.8 (after Clark and Smith, "Leaf Analysis of 
Persimmons", Growing Today, New Zealand Feb. '86, 
pp. 15-17) illustrates the seasonal levels of important 
plant nutrients (as 90% dry matter) and 
micro-nutrients (as micrograms/gm) in leaf. The 
figures illustrate several things: 

potential for early intervention in adjusting levels 
(before it is too late to save the crop). 


Type 1: Zinc. Iron. Copper : high in new spring 
growth, falling over summer, and finally (as leaves are 
lost to the tree) becoming more concentrated in the last 
leaves, as uptake by roots concentrates these elements 
in the last leaves. 

Type 2: Boron. Manga nese. Calcium: increase 
throughout the whole season of growth. Not "mobile" 
once in the plant. 

Type 3: Nitrogen. Phosphorus, Sulphur : rapid 
early uptake, then a gradual decline over the season. 

T ype 4: Potassium : remains steady over the year, 
then declines as wood storage and root reserves build 

As persimmons are not atypical plants, these 
findings have implications for pre-emptive adjustment 
(e.g. by foliar sprays), and selective mulch (e.g. the 
season at which leaves are taken for compost). 




BelwiOur of basic nutrients in the leaf analysis of a deciduous tree 
(here a persimmon). Levels vary across the growing seaMn^ 

| (After Growing Today. NZ Tree crops Association. Feb. 1986 (See 


pp16-7 for actual graphs)). . . 

A Cu, Fe. Zn, P. N. and S. Similar curves, slight increases in late 

B8 Mn Mg, and Ca The non-mobile elements increase steadily in 

concentration; Mg is not normally regarded as non-mobile. 

C K. Remains fairly steady, and is ‘withdrawn- from leaves m autumn 


TABLE 8.7 


use: Read the first set of choices (A), make 
one. and follow on to the letter group in the righthand 
column. Then make a second choice (or find the 
answer). Some remedies follow, and are given under 
the numbers in brackets {). 

First Ch oi ces: _ Go to 

A. • Leaves, stems, or leaf stalks are affected ....B 

• Flowers or fruits are affected.M 

• Underground storage organs (roots, bulbs, 

tubers, etc.) are affected .N 

• Whole field or row shows patchy or variable 


B. • Youngest leaves show most effect, or early 


• Oldest leaves or later whole plant 


C. • Pale yellowish or white patches on the 

leaves .D 

• Pale patches not the worst symptom, but death of 
tips or growing points, or storage organs 

affected. H 

D. • Leaves uniformly colour-affected (yellowish or 

pale), even the veins, poor and spindly plants 
(especially in heavily cropped or poor leached sandy 
areas, acid or alkaline.{ 1 } 

• Leaves not uniformly affected, veins or centres 

still green .E 

E. • Leaves wilted, then light-coloured, then start to 

die. If onions, crop is undersized. If peas, seed in pods 
barely formed, matchhead size. Coastal sands. Black 
sheep in flocks may show a brown tinge to wool and 
are often used as "testers".(2) 

• Wilted and dying leaves not the problem.F 

F. • At first, colour loss is interveinal (between veins), 

and only later may include veins. Mature leaves little 
affected, dying not a feature, and common on calcar¬ 
eous or coral atolls, desert soils. Distinct yellowing 
(See also J).{3} 

• Veins remain green, pale areas not so yellow, 
often whitish or lack colour. G 

G. • Areas near veins still green, affected leaf areas 

become transparent, brown, or start to die. Young 
leaves first affected. Peas and beans germinating in 
soil show brown roots and central brown area on leaf 
cotyledons. pH usually >7.0.{4} 

• Leaves smaller than normal, stems shortened, 

growth retarded. Beans and sweet corn, several tree 
seedlings most affected. Soils acid, leached sands, 
alkaline, high in humus, coastal. Leaves may develop a 
rosette appearance, bunchy tops.{5} 

H. • Plants brittle, leaves die or are distorted, growing 
points die. stems cracked, rough, short between 
leaves, split lengthwise (cabbages), cracked (celery). 
Probable on acidic sands, or on heavily-limed 

high-humus soils.{6} 

• Plants not brittle, but stunted, tips dying, feeder 
roots die, and leaf tips and terminal bud margins dying. 
Cabbage or cauliflower have young cupped or dead 
margins; old leaves all right. Young infolded leaves 
brown-edged, rotting (jelly-like decay). Check on 
over-watering, excess Na, K. Mg in water, or in 

or dolomite. Tomatoes show blossom end rot.{7} 

I. • Plant with marked yellow (chlorosis). J 

• Yellowing not the main problem; leaves 
brown-edged or purple. L 

J. • Yellowing between veins or on margins of 

leaf. K 

• Yellowing affecting whole plant, ranging from light 

green to yellow; plant gets spindly, older leaves drop 
off. Prevalent in cold peaty soils, leached sands, soils 
subject to waterlogging. Turnips show purpling on 
leaves. Plants flower or mature early.(8) 

K. • Margins yellow, or blotched areas which later join 

up. Leaves can be yellowed or reddish, purple, 
progressing to death of leaf area. Later, younger leaves 
affected. Affected areas curl or become brittle, 
brownish. Common on acid sandy or soil with high K or 
Ca readings. Growth slow, plant stunted.{9} 

• Interveinal yellowing, looks at first like N 

deficiency . Old leaves blotched, veins pale green, leaf 
margins rolled or curled, progresses to younger leaves. 
Leaf margins of cabbage, cauliflower can die. leaving 
central tissue only ("whiptail"); cauliflower will not form 
curds. Common on acid or leached alkaline soils, e.g. 
shellsand dunes, corals. Difficulty in establishing 
clover, legumes.{ 10 } 

L. • Leaf margins brown, scorched, can cup down¬ 

wards. dying target spots appear in leaves; spots have 
dark centres, yellow edges; general mottled 
appearance. Growth reduced, first on young matured 
and then on older leaves, finally to young leaves. May 
appear late in plant s growth if a root crop (K is 
translocated to roots). Leached acidic or organic clay 
soils. Tomato leaf margin pale.{11} 

• Leaves wilt, droop, die at tips and edges: 

Sodium excess. 

• Leaves dull, dark green or red-purple, especially 

below (under-surface) and at the mid ribs. Veins and 
stems may also purple, growth is much reduced. 
Common in very acid, alkaline, dry. cold, or peaty 
soils.{ 12 } 

• Leaves at tips wilt early as soil dries out. then 
become bronze, then die. Not often seen. Check water 
supply, salt content of soil: Chlorine excess. 

M • Fruit rough, cracked, spotted, few flowers. 
Tomatoes with internal browning, seed chamber open, 
uneven or blotchy ripening, stem end reddening. On 
acid soils, leached sands, humus-rich and limed soils. 
Terminal buds may die and laterals then develop. Top 
leaves thicken, can roll from tip to base.{6} 

• Fruits rot on blossom end (opposite stalk), or 

show sunburnt dark areas there. Affects tomato, 
peppers, watermelons.{7} 


N. • Internal dying or water-soaked areas, uneven in 
shape (in beet, turnip, rutabaga il soil acid, leached, or 
with free lime.{6} 

• Cavities in root core, then outside collapses as 

pits; common in carrots, parsnips on acid leached soils. 
Roots may split open.{7} 

O • Areas of affected crop test acid; soils may be 
sandy; pH < 5.5: Acid: Try lime 

• Areas of crop test alkaline: pH > 7.5 : Alkaline: 

Try Sulphur. 

• Soil at depth mottled, smells of sulphur: 
waterlogged: Arrange drainage. 

• Leaves tattered and dying at crown. Salt winds: 

Try shelter. 

• Check for viral disease in grasses: Try a plant 



First, keep a fertiliser diary for your garden, and leave 
it for the next person. Tell them what you have done for 
the soil. 

• If you are on leached (washed out) sands, dig up 
your garden beds, place a plastic sheet liner below, 
then add a bucket or so of clay and a handful of 
dolomite per square metre. Also, try a soil gel. Then 
add compost, and a complete fertiliser like blood and 
bone. Mulch thickly and replant, then return to the Key 
if symptoms recur. 

• If you are on peats, or have piled on the compost, 
add some urea or blood and bone, raise your beds, 
and lime the area. 

• If you have lots of lime in the soil, or are on coral 
sands or dry desert coasts with calcrete, spray weak 
zinc and copper sulphates on plants, iron sulphates in 
very dilute solutions (12 g /10 square metres with lots 
of water), or add it to a liquid manure. Make pits of 
compost and grow on the edges of these, use sulphur 
at about a handful per square metre, or add trace 
elements and sulphur to compost pits. Or. lay a sheet 
of plastic on the ground, build up logs around this to 25 
cm high, and fill the area with humus (compost plus 
50% sand), then mulch heavily. Add blood and bone. 
On atolls, dig down to near water table and then mulch 
thickly (make a big growpit 3-4 m wide by 10-12 m 
long by 3 m deep). Use any mulch, especially 
Casuarina. palm, house wastes. 

{1} Sulphur. Add plain sulphur (not of medical 
quality) at one handful per square metre. If you are 
near a city, you could have enough from fallout! 

(2) Copper. Add as fine-crushed ore. or in water as 
copper sulphate at 7 kg/hectare or spread (1 g/square 
metre) every 5=7 years- 

{3} Iron. Try sulphur first, then if necessary add iron 
sulphate or spray foliage with very dilute iron solution. 
Bury old iron in humus pits near trees (e.g. pieces of 
galvanised iron, old wire or car parts). 

{4} Manganese. Try sulphur first, then use very dilute 
foliar spray of manganese sulphate. 

(5) Zinc. Add zinc oxide in acid areas, sulphate in 
alkaline, also sulphur in alkaline areas. Zinc at 7 
kg/hectare or equivalent every 7-iQ yea'S, 

(6) Boron. Be careful not to add too much; it is 
poisonous in large quantity. First, lime acid areas and 
peats, and add sulphur to alkaline areas. If this doesn't 
work, add borax (sodium borate) at 1 gram/square 
metre and try cabbages to test reaction. Try not to buy 
detergents with "borates': they can poison your soil. 
Boron excess (poisoning) can occur on sea 
sediments, and are common in reclaimed marine areas 
(Holland). Raise garden beds. lime, and flush out with 
fresh water. 

{7} Calcium. Use lime as limestone in areas where 
manganese is plentiful, dolomite if not. or as cement 
powder in deep red hot tropical soils, then continue to 
add mulch and use lime only if deficiencies occur. Use 
gypsum in alkaline salty soils, then flush with fresh tank 
water and continue to use lime. Bone, bamboo mulch, 
buckwheat straw are all calcium sources. 

{8} Nitrogen. Make sure the soil is well drained to 0.5 
m for vegetables, 1-2 m for trees. Check for cobalt 
levels, deficiency. If legumes are used, make sure they 
are innoculated. and that manganese levels are not too 
high. If all this is satisfactory, add dilute urine (20 parts 
water :1 part urine), ammonium sulphate in alkaline 
areas, or use legume mulches or interplant (about 48 
small acacia or tagasaste trees per one fourth acre will 
do). Use compost, then surface mulch. Build up worms 
and soil life, use dilute bird manure. Don't overdo it. or 
nitrates will build up in green plants and kill your kids or 
piglets with bluebaby syndrome. Just relieve the 
symptoms, then get good soil life going. 

Use cobalt for severe nitrogen deficiency, poor clover 
growth or establishment in peaty or coastal soils. If 
manganese is high, just add lime to balance this soil 
(one handful per square metre), or in alkaline soils 
spray on at very low dilutions at 1 g /10 square metres 

every iQ years or so, 

{9} Magnesium. Check if potash is not too high, or 
add clay to sandy acid soils (plenty of magnesium in 
most clays). Use dolomite for first dressing, then 
limestone. Epsom salts were used around citrus by 
old-timers. Or dilute it in water for foliar spray in very 
severe deficiency situations. 

(10) Molybdenum. Get some sodium molybdate, 
about 10 g. and mix well with 5 kg of sand. Take 1/100 
of this (weigh the sand), and put it on per square metre 
every 10 years . 

(11) Potassium. Use ashes on green crop, diluted 
urine in early growth, then build up mulches, including 
dried or fresh seaweeds, flue dusts from cement works 
(fly ash), also "teas" of bird manures, comfrey. 
Potassium is found in the mineral kainite (20-25%) 
potassium) in evaporite deposits of deserts. 

{12} Phosphorus Bring pH to 6-6.5 or thereabouts, 
using lime in acid soils and humus in alkaline. Use 
bone meal, bury bones, or use tested rock phosphate 
free of cadmium or uranium. Stop deep digging and 
start mulching with least soil disturbance (build up 
narrow beds). Encourage soil life, add mulch on top. 
water with comfrey "tea", dilute bird manure on the 
leaves of plants. Keep this up each time symptoms 
appear; they will eventually disappear if you have clay 
in the beds (add some if not). If you have high-iron 
clays, you will need a lot of bone meal to start with, but 
it will slowly release later on. If desperate, use a few 


handfuls of superphosphate per square metre, then 
continue with other sources. Feed a patch of comfrey 
with bird manure and make a comfrey tea in a drum of 
cold water. Water the plants with this. All animal 
manures (including yours) contain some phosphorus. 
Calcined (roasted) rock phosphate is effective on acid 
soils in high rainfall. 

(13) Chlorine poisoning. Sue your Council, or let tap 
water stand with a handful of lime in it for a day. then 
use on the garden. Don't take a shower! 

{Developed and modified after a format developed by English, 
Jean E. and Don N. Maynard. Hortscience 13(1). Feb. 78. 
and with data from the author and Handreck. Kevin A.. 1978. 
Food tor Plants. CSIRO Division of Soils.) 

The present testing method used on specific soil types 
is to sow down mixed legume (clover), Brassica. and 
grass crop (or any important crop that may be grown). 
This sowing is then divided into TRIAL PLOTS which 
are treated at varying levels, and with soil or foliar 
spray amendments, to test plant health and response, 
based on a soil test for pH and mineral availability, or 
on a leaf analysis such as given in Table 8.7. 

For the home gardener, or keen observer, a deliber¬ 
ate wander through the system, and a good key to 
mineral deficiencies may be all that is needed to spot 
specific problems. Problems are in any case rare in 
well-drained garden beds using composts and organic 
moulds, and where one-species cropping is not con¬ 
stantly practised. 

On a broader scale, as in prairie or forest re¬ 
establishment and erosion control, land reclamation, or 
plantation, every practical farmer and forester uses 
TEST STRIPS of light to heavy soil treatments (from 
soil loosening to fertiliser, micronutrient, and grazing, 
cutting, or culling trials). When such field trials (as 
side-by-side strips) are run, it is wise to include typical 
areas of soil and drainage, and to avoid areas under 
trees, on the sites of old stockyards or hay-stacks, 
intense fire scars, watering points, and gateways and 
roads (all of which have minor but special features and 
need a separate assessment from the open field 
situation). I have often noted, for instance, the 
colonisation of chicory, thistles, and tough and 
deep-rooted weeds on the inhospitable areas of old 
roads and trafficked areas; this sort of data is of use for 
some cases, but does not need to suggest that we 
compact a whole field in order to grow chicory, rather 
that chicory is a useful pioneer of compacted soils. 

Plant response on the test strips, which can be as 
little as 1 % of the total acreage, may quickly indicate 
how modest and innovative soil treatment, minute 
amounts of micronutrients, or the timing of grazing or 
browsing can be managed to give good effects at least 
cost. There is no assurance as certain as the actual, 
assessed plant response. To see two small plots of 
pines, coconuts, or cabbages side by side, the one 
healthy, vigorous, and productive, and the other 
(lacking a key nutrient or on compacted soils) stunted, 
sickly, and unproductive, is a definite guide to future 
treatments. The same sort of trials are applied to plant 
mixtures or polycultures, pest controls, and the 
benefits or otherwise of mulch for a specific soil or 

Assessment can be casual (in clear-cut cases), or 

analytic and careful where only slight differences 
appear. Such test strips are best securely marked by 
stout pegs for long-term visits, as effects of some 
treatments persist, or become evident, over several 

Not until trials are assessed is it wise to widen the 
area treated, although in commonsense it may always 
be wise to add humus or manures to non-peaty soils, 
or dolomite to acid sands. In alkaline and heavy clay 
soils, trace elements may become insoluble, and these 
are best added as foliar sprays to mulch or green crop, 
or to trees. 

_ &15 _ 


In any local area, the composition, shape or size, and 
distribution of the plants give many clues to soil type, 
depth, and extrinsic factors. Some specific factors 
indicated are: 

SOILS: 1 Depth 

2 Water reserves 

3 pH 

4 Mineral status (see preceeding section) 

SITE: 5 Fire frequency 

6 Frost 

7 Drainage 

8 Mineral deposits and rock type 

9 Overgrazing and compaction of soil 
10 Animal (macrofauna) effects 

1 SOIL DEPTH: Shallow soils dry out quickly and 
hold few nutrients. A very good indication of soil 
depth is to look at one species of tree (e.g. Acacia, 
Prosopis, honey locust) over a range of sites; a “height 
and spread" estimate will reveal areas of deeper soils 
where the largest specimens grow. The same species 
will be dwarfish on shallow soils of the same 
derivation or rock type. 

2. WATER RESERVES. Deep-rooted trees which 
need water—the large nut trees and candlenuts 
(Aleurites) are good examples which occur naturally 
only in well-drained but water-conserving sites— 
often show water-lines not associated with valleys, 
and stand over springs or aquifer discharge areas. 

In sands, a great variety of deep-rooted shrubs and 
trees indicate where a clay base lies at 1-2 m down. 
This situation is common on desert borders and hills in 
drylands. In brief, large tree stems reveal well- 


watered sites, small stems drier sites. Armed with 
these observations, we can create sites by water 
diversion and select sites for large trees or shrubs. 

3. pH: Sorrel and oxalis in pastures may indicate 
compact or acid conditions, whereas several fen and 
limestone species establish in alkaline areas; large 
snails and dense snail populations occur only over 
alkaline soils or in alkaline water. No snails or minute 
species occur in acid water (pH < 5.0). In the garden, 
our cultivated plants demand acid or alkaline soils, e.g. 
Alkaline intolerant (pH 4.5-6.0): 

• Blueberry 

• Chicory 

• Chestnut 

• Endive 

• Potato 

• Fennel 


• Coffee 

• Rhubarb 
Alkali tolerant : 

• Oats 

• Kale 

Ac id into ler a nt (pH 7.0-8.5): 

• Cauliflower 

• Cabbage 

• Asparagus 

• Green peas, bush beans 

• Celery 

• Leek' 

• Beet • Lucerne 

• Onion 

• Chard 

• Parsnip • Broccoli 

• Spinach 

• Lupin 

• Oats 

• White clover 

This will have a profound effect on our home garden 
planning, but providing garden soils are mulched, and 
a little lime is added to compost, all plants thrive in 
high humus soils supplied with some lime at modest 
levels. It is the perennial species that may need more 
care in site selection, or with mulch and compost in 
alkaline areas. Almost all our pollutants, and many of 
our fertilisers, tend to make soils acid, as does 
continued cropping or over-grazing. 

5. FIRE FREQUENCY. East-west ridges often reveal 
abrupt species changes at the ridge wherever fire 
occurs. Fire produces dry. scrabbly, summer- 
deciduous, thick-seeded species; lack of fire develops 
broadleaf, winter-deciduous, small-seeded plants with 
thin seed capsules and a deep litter fall. 

Cross-sectional cuts of trees will reveal fire scars as 
gum pockets or charred sections, and these can then be 
counted to get the "fire frequency" of the site (Figure 
8.9). If tree stem sections are marked for directions 
before sampling, the direction of fires can also be 

• Shallot 

• Watermelon 

• Rye 

, AT 

% Aik/UT S 

Mk yeAK. 




Show frequency and severity of fires on any one site 

6. FROST. Many species of trees and plants will 
indicate frost-lines; it is a matter of observing local 
flora, or planting frost-susceptible species down a hill 
profile to measure frost intensity. Tomatoes, bananas, 
and potatoes are all frost-sensitive and will reveal 
frost-lines on hills in subtropics and deserts. 

7. DRAINAGE. Mosses, sundews, and fine-leaved 
heaths indicate poorly-drained soils, as large trees 
such as chestnuts (which require 2 metres of 
well-drained soil) indicate good drainage; these 
indicators assist survey before pits are dug or drainage 

8. MINERAL DEPOSITS. Davidov (Sputnik. 12 Dec. 
'79) gives data on plant systems over mineral deposits 
(for Russia). The analysis of plant residues often 
indicates concentration of ores in the underlying soil or 
rock. Lead and copper-molvbdate are so indicated. 
Leaves or humus from birch, cherry, honeysuckle, St. 
John's Wort, wormwood, juniper, and heather reveal 
the above lodes plus tungsten and tin concentrates. 
"All purpose" plants so discovered are: 

Rue or violets.zinc 



Milk vetch.selenium and uranium 

Russian thistle.boron 


Honeysuckle.silver and gold and silica 

General plant ash analysis may reveal more s pecific 
plant-ore associations. This has further implications for 
the rehabilitation of mine waste areas, and also to 
select plant sources for the supply of trace minerals in 
compost. As plants have the ability to both concentrate 
and tolerate unusually high levels of specific minerals, 
there seems to be a field here for the biological 
concentration (and subsequent removal) of metallic soil 
pollutants like lead or uranium, and the use of 
concentrator plants to mine or collect locally rare trace 


elements. In fact, some patents have apparently been 
granted for mining gold deposits using banana or 
citrus plants deprived of some common elements 
(potash, phosphate); their leaves then concentrate 
sparse deposits of gold. 

Oysters will concentrate zinc (to 11% dry weight, an 
emetic dose), abalone concentrate cadmium, and 
several large fish concentrate mercury and biological 
poisons from corals (to inedible levels). There are 
obvious implications for the removal, collection, or use 
of such species—element relationships, and lead, 
cadmium, or mercury levels in fish or plants need 
careful monitoring for public health reasons. 

Both the levels of grasshopper and pasture grub 
activity (high on overgrazed landscapes) and the 
presence of patches of poisonous, inedible, thorny, and 
unpalatable plants (e.g. Sodom apple, oxalis, 
capeweed) indicate an over-stocking problem or range 
mismanagement. The effect is a synthesis between 
changing soil conditions, plant stress, and the heavy 
selection by livestock of palatable species, so favouring 
the survival and spread of spiny or inedible species. 
Too often, the pastoralist blames the weeds and seeks a 
chemical rather than a management solution; too 
seldom do we find an approach combining the sensible 
utilisation of grasshoppers and grubs as a valuable 
dried-protein supplement for fish or food pellets, and 
a combination of soil conditioning, slashing, and 
de-stocking or re-seeding to restore species balance. 

10. MACROFAUNAL EFFECTS. The site of a sea¬ 
bird rookery, a rabbit warren, the ground nest of a 
goose or eider clutch, the pellet-pile of an owl, or the 
decay of a large carcass will cause a sudden and often 
long-term change in the immediate vegetation, as will 
termite mounds and harvester-ant colonies. Once such 
sites are recorded, and the plant assembly identified, 
similar sites can be located and recognised. The data 
can be used as an aid to conservation, an indication of 
soil drainage (rabbits choose good drainage), as a 
result of specific nutrient supply (guano on seabird 
rookeries), or as a way to establish tree clumps 
following natural indicators. 

A large proportion of wind-blown, nitrogen-loving, 
and inedible plants, or plants earned by birds as seed, 
depend on the specific habits of birds or mammals, on 
their dung, or on soil disturbances. The role of animals 
in the distribution of plant seed, and plant root 
associates, is well-recognised; their role in soil change, 
less commonly noted. 

_ SA6 _ 


In pioneering the rehabilitation or stabilisation of soils, 
many of the local deficiencies in soils can be overcome 
by seed pelleting, which is a process of embedding 
seed in a capsule of substances that give it a good 

chance of establishment despite soil deficiencies in 
local sites, or microsites. 

• SEED PRETREATMENT. If seeds have thick coats, 
or need heat or cold treatment or scarification to break 
dormancy, they must be treated before pelleting. 

• INOCULATION. Purchase and inoculate legume 
seed with their appropriate microbial or fungal spores. 
Soak the seed in inoculant solution, then dry the seed. 
Mix dried seed with a primary coat as below. 

• PELLETING. Use a lime, clay layer, and a trace of 
fine rock flour, calcium, or phosphate mixed into a 
damp but plastic slurry around the seed. This is then 
extruded (e.g. via a meat mincer with the cutting 
blades removed) to a shaker table or tray covered with 
dust, and on a slight incline. Dust is added as needed 
to dry and shape the pellet, or to set a desirable size of 
pellet (Figure 12.18). 

The dust, or outer pellet coat, should incorporate a 
soil conditioning gel or polymer, a colloid-forming 
substance (fine graphite), a bird repellent (green dye 
helps repel birds), an insect repellent such as powdered 
neem tree leaf (Azadirachta indica or Melia azedarach) or 
diatomaceous earth, and perhaps some swelling clay 
such as bentonite. 

Pellets are now dried and scattered, drilled, or sown 
on sites to await rain. The protected seed germinates 
when the pellet absorbs water, and the emerging root 
finds its nutritional needs satisfied, while the root 
associates also become active in nutrient transfer to the 

The same vibrating table that we use to pellet seed 
serves, when fitted with screens, to clean and sort seed 
from the soil below trees or from seed and husk 
mixtures, and the mincer can be returned to the kitchen 
none the worse for wear. Fukuoka achieves the same 
result by pressing seed-clay mixes of grains through a 
coarse sieve, onto a dust-filled pan which is shaken to 
round off the pellets. 

_ 817 _ 


As all else depends on a stable and productive soil, soil 
creation is one of the central themes of permaculture. 
Soil erosion or degradation is, in fact, the loss of 
production and hence of dependent plants and 
animals. Soils degrade in these ways: 

• Via wind: by dust storm and the blow-out of 
dunes and foreshores. 

• Via water flow by sheet erosion (a generalised 
surface flow off bare areas and croplands), gully 
erosion (caused by concentrated flow over deep but 
unstable sediment), and tunnel erosion (sub-surface 
scouring of soils below). 

• Via soil collapse or deflocculation following 
increased salt concentrations in clay-fraction soils. 

Thus, the placement of windbreaks, tree crops, and 
fast-spreading grasses stabilises erosion caused by 


wind, while permanent crop, terracing forestry, and (in 
the case of gullies) diversion and spreader drains plus 
gabions help reduce or heal scoured areas. Tunnel 
erosion may call for de-stocking, contour drainage, 
and the establishment of deep-rooted plants, while the 
problems of desalting need the combined factors of 
reafforestation (to lower groundwater tables) following 
deep interceptor drains to cut off salt seepages in 
surface soils (see Chapter 11). 

Erosion follows deforestation, soil compaction, 
disturbed soil-water balance (increased overland flow 
and rising water tables or salt seepages), overgrazing, 
plough agriculture on the broad scale, episodes of high 
winds or rains in drought periods, or severe 
disturbance caused by animal tracks, roading, and 
ill-advised earthworks. 

Insofar as landscape design is concerned, soil erosion 
repair is the priority wherever such erosion occurs. 
Apart from the physical factors, no designer, or nation, 
can ignore the economic or political pressures that 
inevitably create erosion by requiring or permitting 
inappropriate land use and forcing production or 
over-production on to the fragile structure of soils. 
Third world debt and western world over-production 
are both primary factors in soil collapse. In a 
conservative society, the very basis of land use 
planning would encompass the concept of permitted or 
restricted use of soils, carefully plotted in regions 
following analyses of slope, soil stability, minimal 
forest clearing (or reafforestation), and permitted 
maximum levels of crop production, or livestock 
density, following the procedures of good soil 

In assessing erosion in the U.K., Charles 
Arden-Clarke and David Hodges (New Scientist 12 Feb 
'87) point out that "many of the recent outbreaks of 
severe erosion are clearly linked to falling levels of 
organic matter in the soil... the more organic matter 
there is in the soil, the more stable it is." This stability is 
because of good soil structure and infiltration of water, 
whereas an inorganic soil may break down under rain. 
With the following increase in overland flow, most 
soils will then erode as rills or gullies, or the destroyed 
surface can powder and blow away without organic 
matter to bond it. 

On many delicate soils (over chalks) the only answer 
is to replace crops with pasture or forests. Intensive 
arable use and winter cropping both create more 
erosion. The very radical conclusion is that mulching, 
green manure, grass leys on rotation, hedgerows, and 
minimal cultivation are not only urgent but imperative. 
Thus, "the time to examine the organic (farming) 
approach has passed, the time to adopt it has arrived." 
(ibid.) At long last, some scientists are saying that 
enough evidence is enough; we need to turn to known 
effective land management based on permanence and 
organic methods. This will take the combined good 
will of farmers, scientists, financiers, and consumers. 



Careful gardeners take care not to break up, overturn, 
or compact their valuable soils, using instead raised 
beds and recessed paths to avoid a destruction of 
crumb structure. Responsible farmers try to govern the 
speed and effect of their implements in order to pre¬ 
serve the soil structure, and can get quite enthusiastic 
about a dark, humus-rich, crumbly soil. We seldom 
give farmers time or money to create or preserve soil, 
but expect them to live on low incomes to serve a 
commodity market, whose controllers care little for 
soil, nutrition, or national well-being. 

No matter on what substrate we start, we can create 
rich and well-structured soils in gardens, often with 
some input of labour, and always as a result of adding 
organic material or green manures (cut crop). No 
matter how rich a soil is, it can be ruined by bad 
cultivation practices and by exposure to the elements: 
wind, sun, and torrential rain. 

Worms, termites, grubs, and burrowers create soil 
crumbs as little bolus or manure piles, and they will 
eventually recreate loose soils if we leave them to it in 
pasture. But we also have other tools to help relieve 
compaction; they can be explosives, special 
implements, or roots. 

We use the expansive and explosive method rarely, 
perhaps to plant a few valuable trees in iron-hard 
ground by shattering. People like Masanobu 
Fukuoka 1 '- 4 ' are more patient and effective, casting out 
strong-rooted radish seed (daikon varieties), tree 
legume seed, and deep-rooted plants such as comfrey, 
lucerne. Acacias, and eventually forest trees. Much the 
same subsurface shattering occurs, but slowly and 
noiselessly. The soil regains structure, aeration, and 
permits water infiltration. 

A measure of the change wrought by green manures, 
mulch, and permanent windrow is recorded by Erik 
van der Werf (Permacutture Nambour Newsletter, 
Queensland, Dec. 1985 and Mar/Apr 1986). Working in 
Ghana at the Agomeda Agricultural Project, he reports 
on the improvement of crumb structure by measuring 
the bulk density {weight per volume ratio (g/cc) of soil 
samplesl is given in Table 8.8. 

TABLE 8.8 

Improvement in Crumb Structure 

Soil Treatment 




Annually burnt bush 


Bush left 2 years without fire 


Farmland, cultivated 2 years 


Farmland, permanently mulched 
and cropped for 3 years 


’Even with cropping, the mulched soils show how 
humus alone restores good aeration; soil temperatures 
were lower by 10°C, and both crop grain yields and a 
three times increase in organic matter production were 



We can use rehabilitative technology on a large scale, 
followed by the organic or root method, by pulling a 
shank and steel shoe through the soil at depths of from 
18 cm (usual and often sufficient) to 30 or even 80 cm 
(heroic but seldom necessary unless caliche or 
compacted earth is all we have left as "soil"). 

In field or whole site planning, a soil map 
delineating soil types can either be purchased or made 
based on local knowledge and field observation. In 
designing, it helps future management if uses, fencing, 
and recommendations for soil treatment and crop can 
be adjusted to such natural formation as soil types. An 
aid to SOIL TYPING can be found in basic books on 
soils. These publications give practical guides to 
landform, floristics (structural) typing, and soil typing 
and taxonomy (categories or classes of soils). 

We can recommend low-tillage systems, pay close 
attention to water control during establishment, and 
get soil or leaf analyses done. We can also make careful 
trials of foliar sprays, the additions of cheap colloids to 
sands, the frequency and timing of critical fertiliser 
applications (often and little on sands, rarely or as 
foliar sprays on clays). Crops suited to natural pH (it is 
often expensive to greatly modify this factor) and 
rainfall should be selected for trials. Close attention 
needs to be paid to the soil stability and thus the 
appropriate use for soils on slope. 

hi particular, priorities should be set for erosion 
control in any specific soil or on specific sites or slopes, 
and earthworks or planting sequences designed to 
establish soil stability, for if we allow soil losses to 
continue or worsen, all else is at risk. The next stage in 
the design is to assess the capacity of soils for dams, 
swales, foundations, or specific crops (this may need 
further analysis, test holes by auger, or soil pit 

Thus, if we have adopted a pre-determined set of 
values based on soil and water conservation and 
appropriate uses of sites versus erosion and high 
energy use, any site with its water lines and soil types 
noted starts to define itself in usages. 

How we need to proceed in soil rehabilitation is 
roughly as follows: 

1. WATER CONTROL. Drainage and sophisticated 
irrigation are needed to rehabilitate salted areas, and 
soil mounding or shaping to enable gardening in salted 
lands (as explained in Chapter 11 on arid lands). We 
need to rely much more on natural rainfall and water 
harvest than on groundwaters. Drought is only a 
problem where poor (or no) water storage has been 
developed, where tree crops have been sacrificed for 
fodder or fuel, and where grain crops are dependent on 
annual rains. 

Although many sands and deeply weathered soils 
are free-draining, waterlogging can occur wherever 
soil water lies over an impermeable soil layer or where 
water backs up behind a clay or rock barrier; anaerobic 
soil results. Remedies lie in any of three techniques: 

L_Ra^gd gflrden_beds: paths are dug down for 
drains, and beds raised; in very wet areas give paths a 


1:500 slope to prevent erosion. Figure 8.10.A 

2. Deep open drain s every 10-80 m (clay-sands) 
upslope and downslope or on either side of garden 
beds. Figure 8.10.B 

3. Underground pipes (tile drains; fluted plastic 
pipes are best) laid in 1.5 m deep trenches and 
backfilled at 1.5 m (4.5 feet) deep and from 10-80 m 
(32-262 feet) apart, starting on a drain or stream and 
with a gentle fall (1:1000-1:600) to the ridge. Figure 

Water retention in soil is now greatly aided by 
long-term soil additives. These are gels which absorb 
and release water over many cycles of rain. This is a 
practical system only for gardens or high-value tree 
crop (where the cost amortises). 

2. SOIL CONDITIONING. Compacted, collapsed, 
and eroded soils need rehabilitative aeration, and a 
change in land use. 

3. FERTILISATION. We can reduce and replace past 
wasteful or polluting fertilisation by sensible light trace 
element adjustment via foliage sprays if undisturbed 
soil systems and permanent crop have been developed. 
Foliar spray of very small amounts of key elements 
greatly assists plant establishment, as does seed 
pelleting using key elements deficient in plants locally. 
We may then be able to utilise much of the phosphate 
that is locked up in clays, and using legumes, create 
sufficient nitrogen for food crops from sophisticated 
interplant and green manures. 

older varieties of both annual and perennial crops will 
yield with less fertiliser and water applications than 
will more recently-developed varieties. There is a 
growing trend amongst farmers and gardeners to 
preserve and cultivate these varieties not only for the 
reasons above, but also for flavour. Many older apple 
varieties, such as some of the Pippin and Russet types, 
are more flavourful than, say, the market-variety Red 
Delicious. There is still a large diversity of food crops 
left in the world; the key is to grow them and to 
develop a regional demand. Many older apple or 
wheat species are not only pest-resistant, but have 
higher nutritive value, and can produce well in less 
than optimum conditions. 

There are different species of plants that can live in 
almost any type of soil, starting the process back to 
rehabilitation. It is often the case that so-called noxious 
weeds will colonise eroded landscapes, beginning a 
slow march towards stabilisation; these can be used as 

Soils can be created or rehabilitated by these basic 

• Building a soil (at garden scale); 

• Mechanical conditioning; and 

• Life form management (plants and macro- or 


Gardeners normally build soil by a combination of 

three processes: 

1 Raise or lower beds (shape the earth) to facilitate 
watering or drainage, and sometimes carefully level 
the bed surface; 

2 Mix compost or humus materials in the soil, and 
also supply clay, sand, or nutrients to bring it to 
balance; and 

3 Mulch to reduce water loss and sun effect, or 

Gardeners can. by these methods, create soils 
anywhere. Accessory systems involve growing such 
compost materials as hedgerow, herbs, or soft-leaf 
plots, or as plantation within or around the garden, 
and by using a combination of trellis, shadecloth (or 
palm fronds), glass-house, and trickle irrigation to 
assist specific crops, and to regulate wind, light, or heat 

By observing plant health, gardeners can then adjust 
the system for healthy food production. Many 
gardeners keep small livestock, or buy manures, for 

this reason. 

Large-scale systems (small farms) cannot be treated 
in the above way unless they are producing high- 
value product. Normally, farmers create soils by 
broadscale drainage or by soil "conditioning". As most 
degraded soils are compacted, eroded, or waterlogged, 
they need primary aeration (by one of the many 
available modern machines, or by biological agents), 
then careful plant and livestock management to keep 
the soil open and provided with humus. 

Daikon radish, tree or shrub legumes, earthworms, 
root associates for plants (rhizobia) all aerate, supply 
soil nutrient, or build soil by leaf fall and root action. 
The management of livestock for least compaction and 
over-grazing is part of the skill of soil building and 
preservation. Many organic farmers introduce worm 
species to pastures as part of their operation, and sow 
deep-rooted chicory, radish, or comfrey for green 


SOIL TREATMENT ON COMPACTED SITES— At the end of winter, or in autumn after some rain. 


On the common degraded soils of marginal areas, we 
can observe compacted, eroded, lifeless soils; they are 
overgrazed and often invaded by flatweeds and 
non-forage species of plants. They are boggy and wet 
in winter, and they are dry, cracked and bony in 
summer, having little depth. The reconstitution 
proceeds as follows: 

when the soil will carry a tractor, a chisel plough is 
pulled 5-10 cm (2—I inches) deep over the area, either 
on contour parallels or on low slopes, starting in the 
high valley bottoms and driving slightly downhill to 
the ridges. Unless there are absolutely no legumes or 
grasses already growing, no extra seed is applied. The 
response is increased penetration of roots, germination 
of seed, and a top-growth of pasture. 

FIGURE 8.11. 

A Chisel plough shank (trom the Wallace Soil Conditioner). 

B In pasture 3 or 4 sequences with increasing depth ot tmes creates 
deep (18 cm) humus soils over 1-2 growing seasons 


A chisel plough or soil conditioner is a rectangular 
steel frame (tool bar) towed by tractor or draught 
animals, to which a number of shanks are attached. 
These are narrow-^dge (axe-edged) forward-curved 
vertical flat bars to the point of which a slip-on steel 
shoe is attached. The shanks clamp to the tool-bar 
frame, and the points to the shank. Even one 
implement of 5 shanks (25-50 b.h.p. tractor) covers a 
lot of country. There are now at least six or seven 
makers of soil-loosening machines, in the USA, 
Europe, and Australia. 

Geoff Wallace has produced a soil conditioner of 
great effectiveness. A circular coulter slits the ground, 
which must be neither too dry nor too wet, and the slit 
is followed by a steel shoe which opens the ground up 
to form an air pocket without turning the soil over. 
Seed can be dropped in thin furrows, and beans or 
corn seeded in this way grow through the existing 
grass. No fertiliser or top-dressing is needed, only the 
beneficial effect of entrapped air beneath the earth, and 
the follow-up work of soil life and plant roots on the 
re-opened soil. 

This new growth is then hard-grazed, or cut and left 
to lie. The plants, shocked, lose most of their root mass 
and seal their wounds. The dead roots add compost to 
the soil, as does the cut foliage or animal droppings, 
giving food to the soil bacteria and earthworms, and 
softening the surface. As soon as the grazing or cutting 
is finished, chisel again at 23-30 cm (9-12 inches), on 
the same pattern as before. Graze or cut again, chisel 
again at 23-30 cm. Graze or cut. 

During this process, often a matter of a one-year 
cycle, the pasture thickens, weeds are swamped with 
grasses and legumes, myriad roots have died and 
added humus, and thousands of subsurface tunnels 
lead from valley to ridge, so that all water flows down 
into the soil and out to the ridges. Earthworms breed in 
the green manure, bacteria multiply, and both add 
manures and tunnels to the soil. A 23 cm (9 inch) 
blanket of aerated and living soil covers the earth. 

Dust, deep roots, rain, and the bodies of soil 
organisms all add essential nutrients. The composted 
soil is, in essence, an enormous sponge which retains 
air and water, and it only needs a watchful eye and an 
occasional chiselling in pasture (or a forest to be 
planted) to maintain this condition. 

If tree seed, soybeans, millet or other crop is to be 
planted, the sequence is as follows: after a few hard 
grazings or mowings, a seed box is mounted on the 
chisel plough frame, and the seed placed in the chisel 
furrow; the grazing or mowing follows germination of 
the seed. These new plants (sunflowers, millet, melons) 
grow faster than the shocked pasture, and can be let 
go, headed, or combine-harvested before the grasses 
recover. There is never any bare cultivation, and grain 
growers can move to a minimum tillage method of 
cropping, with fallows of pasture between crops. 

Soil temperature is greatly modified, as is soil water 
retention. Geoff Wallace (pers.comm.) recorded as much 
as 13°C (25°F) increase on treated versus untreated 

soils in autumn. This increased temperature is 
generated both by the biological activity of the soil and 
the air pockets left by the chisel-points at various 
depths, and enables earlier and more frost-sensitive 
crops to be grown. 

Nodulation (of nitrogen-fixing bacteria) is greatly 
increased, as is the breakdown of subsoil and rock 
particles by carbonic acid and the humic acids of root 
decay. Methane generated from decay aids seed 
germination, and water (even in downpours) freely 
passes into, not off, the soil. After a year or so. vehicles 
can be taken on the previously boggy country without 
sinking in. Drought effects are greatly reduced by soil 
water storage. 

Water, filtered through soil and living roots, runs 
clear into dams and rivers, and trees make greatly 
increased growth due to the combined factors of 
increased warmth, water, root run, and deep nutrients. 

Fukuoka* 5 ’ (in Japan) uses radish and Acacia ; 
Africans use Acacia albida or Glyricidia ; New Guineans 
use Casuarina ; and Mediterranean famers use Tamarix 
for biological "chisel ploughs" where land is too steep 
and stony for implements. Otherwise the "graze or cut 
and let lie" method is still followed. On such difficult 
terrain as boulder fields, dunes, steep slopes, and 
laterites, forests of mixed legume/non-legume crops 
(citrus, olive, pine, oak) are the best permanent 
solution to soil conservation. 

No matter how we aerate soil (or condition it), 
whether with humble implements like a garden fork 
levered slightly, by planting a daikon radish, or by 
sheer mechanical power, we can soon lose the 
advantage of looseness and penetrability by over¬ 
stocking, cropping, heavy traffic, or heavy-hooved 
animals stocked in wet weather. All of these pug or 
compress the soil into a solid state again. Final 
solutions lie only in following on with permanent and 
deep-rooted plants (forests or prairies), and by 
maintaining good management (minimum tillage) 

Any reduction in cultivation saves energy and soils, 
and wherever no-tillage systems can be devised, and 
heavy hoofed animals kept to a minimum, soil 
structure can be repaired. 

Intense fire, intense stocking, intense cropping, and 
intensive production all threaten soils. Thus, 
mechanical soil rehabilitation can be a one-time and 
beneficial process, or another way to waste energy 
every year. It is the usages that follow on re¬ 
habilitation that are beneficial or destructive to soils in 
the long term. 

Mechanical loosening of soils is appropriate (on the 
broad scale) to almost all agricultural soils that have 
been compacted. Soils with coarse particles, of cinder, 
or dunes do not benefit from or need loosening, and 
very stony or boulder-soil mixtures are appropriately 
rehabilitated not by mechanical but by organic (root 
penetration) methods, as are soils on steep slopes. 
Some soils (like volcanic soils with permanent 
pastures) may never lose structure, and will maintain 


FIGURE 8.12 

A Ideally, chisel lines run 'downhill' from valley fo ridges 

and creates sigmoid (S) curves in the landscape 
C In conditioned landscapes, chisel lines prevent fast run-off and 
absorb overland flow leading water to ridges 

B Here, water flow crosses contours at right angles (no chisel lines) 


free internal drainage after years or centuries of 
grazing. Thus, we use rehabilitative energy only where 
it is appropriate. 

Soil conditioning can be sequential, allowing a year 
between treatments, or all-at-once at 20 cm or so, in 
order to prepare for tree crop planted immediately. The 
time to use implements is also critical, and early spring 
or at the end of a gentle rainy period is ideal, as the soil 
is not then brought up to the surface as dry clods, nor 
collapses back as being too wet. 

There is only one rule in the pattern of this sort of 
ploughing and that is to drive the tractor or team 
slightly downhill, making herring-bones of the land: 
the spines are the valleys and the ribs slope out and 
down-slope (Figure 8.12). The soil channels, many 
hundreds of them, thus become the easiest way for 
water to move, and it moves out from the valleys and 
below the surface of the soil. Because the surface is 
little disturbed, roots hold against erosion even after 
fresh chisel ploughing, water soaks in and life 
processes are speeded up. A profile of soil conditioned 
by this process is illustrated by Figure 8.11. 

There is no point in going more than 10 cm in first 
treatment, and to 15-23 cm in subsequent treatments. 
The roots of plants, nourished by warmth and air, will 
then penetrate to 30 cm or 50 cm in pasture, more in 
forests. For disposal of massive sewage waste-water. 
Yeomans* 5 ' recommends ripping to 90 cm or 1.5 m, 
using deep-rooted trees or legumes to take up wastes. 

1 have scarcely seen a property that would not 
benefit by soil conditioning as a first step before any 
further input. Pasture and crop do not go out of 
production as they do under bare earth ploughing with 
conventional tools, and the life processes suffer very 
little interruption. 

In small gardens, the aeration effect is obtained in 
two ways: 

• By driving in a fork and levering gently, then 
removing it. 

• By thick surface sheet-mulch; worms do the work. 

To summarise briefly, the results of soil rehabili¬ 
tation are as follows: 

• Living soil: earthworms add alkaline manure and 
act as living plungers, sucking down air and hence 

• Friable and open soil through which water 
penetrates easily as weak carbonic and humic acid, 
freeing soil elements for plants, and buffering pH 

• Aerated soil, which stays warmer in winter and 
cooler in summer; 

• The absorbent soil itself is a great water-retaining 
blanket, preventing run-off and rapid evaporation to 
the air. Plant material soaks up night moisture for later 

• Dead roots as plant and animal food, making 
more air spaces and tunnels in the soil, and fixing 
nitrogen as part of the decomposition cycle; 

• Easy root penetration of new plantings, whether 
these are annual or perennial crops; and 

• A permanent change in the soil, if it is not again 
trodden, rolled, pounded, ploughed or chemicalised 
into lifelessness. 

Trees, of course, act as long-term or inbuilt nutrient 
pumps, laying down their minerals as leaves and bark 
on the soil, where fungi and soil Crustacea make the 
leaves into humus. 



Soils cause perhaps 60-80% of all house cracks and 
insurance claims for faulty construction and "tree 
damage". About 20% of the soils we build on will 
subside or heave depending on water content. 
Specifically, black cracking clay, surface clays, and 
red-brown clay loams are subject to swelling and 
shrinking. Solid stone and brick houses are most 
subject to structural failure, with wood-frame and 
veneer less so. 

Over-irrigation of gardens, causing the water table 
to rise, is a primary cause of soil swelling. The removal 
of trees assists this process, as do paved areas, and 
burst or leaking sewage and water pipes. Some 
notorious white or yellow clays collapse as dam walls 
when wetted. It is as well to consult your local soil 
expert for large constructions as trials can be 

While the effects are most noticed to 2 m deep, 
probes to 10 m deep need to be monitored for ground- 
water levels. Soils subside and shrink with excessive 
drying (too many trees too near the house) and swell 
and heave with excessive watering and no trees. 
Adelaide (Australia) is an area where most damaged 
houses are on blacksoil clays, but several other areas 
also suffer these effects, and in some, large buildings 
need to be built on foundations capping deep piles (to 

FIGURE 8.13 

to stabilise house foundations in swelling clay soils 


20 m) sunk to the bedrock or deep into the permanent 
water table (Figure 8.13). 

Most Australian native trees have an efficient water 
removal via roots, so that eucalypts remove 2-3 times 
the water of pines or pasture (to 10 m radius). 
Generally, householders should keep large trees at least 
one half the mature height from the house when 
building in high clay-fraction soils; sands and 
sand-loams are usually stable, as are rotten or 
fractured rock and sandstones. 

_8 1 20_ 


Before we ever learned to cut open the soil, it was 
thoroughly dug, aerated, and overturned by 
multitudes of industrious burrowers. The unploughed 
meadows of Europe and America are as soft as a great 
mattress, and are well aerated due to the moles, 
gophers, worms, prairie dogs, rodents, and larvae 
eternally at work below ground, even under the snow. 
Termites, ants, and crustaceans all do their part. The 
results are obvious from the good soils and great 
productivity of unploughed ground which has not 
been compacted by hooves or machines. 

Termites and ants arc the earthworms of the deserts 
and drylands, carrying tons of organic material to 
underground compost piles, in some of which they 
may grow fungi to feed their colony. The upthrown 
earth, whether from ants or moles, forms a specific 
niche for annuals to seed on, and wind-blown pioneer 
trees to occupy. If birds are the seedscatterers of the 
forest, burrowers are the gardeners. 

Underground and beneficial fungal spores eaten by 
squirrels or wallaby and activated by their digestive 
enzymes break hibernation to occupy new ground and 
help the new roots of acorns and eucalypts to convert 
soil minerals and liquids to food. Gophers and moles 
industriously carry roots and bulbs to secret stores and 
sometimes forget their hoards, so that sunroot, gladioli, 
daffodils and hyacinths spring up in unexpected places 
above ground. This is how comfrey and sunroot 
spread, despite their lack of viable seed. They depend 
not on bees, but on moles and gophers for their 
increase. Foxes eat fruits, and defecate on gopher 
mounds, which are the dug-over areas for new trees. 

Wombats may tunnel, overturn, and even topple 
many hectares of trees, leaving a richly-manured, 
open, and fertile bed for new forest evolutions. Rabbits 
industriously garden thistles, and their tunnels give 
shelter to possum, squirrels, bandicoots, snakes, and 

Worms and crustaceans, in their damp and 
sometimes semi-liquid burrows, move up and down 
like a billion pump plungers, sucking in and expelling 
air (and thus nitrogen) to roots, and in effect giving the 
soil its daily breath. Many creatures mix up special 
mudbrick soils with body secretions, and from 


swallows to termites create homes from stabilised soils. 
Seeds and spores are buried, excavated, hidden, 
activated, and forgotten by burrowers, and recycled to 
life or humus as chance and nature dictate. 

Roots die seasonally, invade and retreat, and leave 
minute or massive tunnels for animals, fungi, and new 
roots to follow. I once tried to dig a parsnip out of 
newly drained swamp ground, following it along an 
old root trace, but gave up after 2 m. I did persist in 
following a 4 cm long engaeid "land crab" or earth 
lobster to 2 m down and 2 m along, and have often dug 
out rabbit and mouse burrows to find their nests, 
mating circuses, air vents, nursing chambers, disposal 
chutes, and escape hatches. Many old gopher burrows 
are filled with plant remains and faecal wastes. 

A few dedicated souls in the history of science, from 
Sir Albert Howard to modern ecologists, try to 
excavate and discover something of roots, but as a 
simple bluegum ( Eucalyptus globulus) can easily 
embrace an underground 1.5 ha, a forest is so complex 
and even intergrafted below ground that the canopy 
seems simple. Many desert plants lead a long and 
sturdy underground life while thin, straggly, and 
ephemeral in air. Some insects, like swift moths 
(Hepialulae) spend 7-8 years underground as large 
bardi grubs (a succulent treat for Australian diggers), 
with only a few days of nocturnal foodless life in air, 
mating and laying eggs before disappearing again to 
the root sheaths and soil, as their near cousins the 
ghost moths and witchetty grubs do in aerial stems. 
The bardi grubs, too, open thousands of shafts to the 
air, and cycle tons of nutrient underground, as do their 
relatives in air and sunlight. Their predators follow 
these hoarders and burrowers below the soil, and hunt 
them in darkness and secrecy. 

The implications for designers are that many of these 
effects may be put to use, or their uses appreciated; it is 
as valid to plant an Acacia for the considerable 
by-product of swift moth or ghost moth larvae as it is 
plant a mulberry for silkworms, and to use moles 
instead of mole ploughs, or gophers as daffodil 
gardeners (unpaid). Even on shores and the bottom of 
lakes and seas, the burrowers work to carry nutrients 
below to roots and to bring up fresh minerals for 
decomposition, while assisting the flux of liquids and 
gases across the surfaces of mud media. 

Roots have their own PENETRATIONS (depth), 
PATTERNS or spread, SCHEDULES, seasonal 
MIGRATIONS to or from the surface, and 
equivalents of deciduous drop or bark decortication, 
dying off and sloughing off root branches and bark. It 
follows that there is a topography of plants 
underground that parallels that of plants in air. There 
are also basic differences, in that special storages or 
fire-resistant organs found underground as 
ligno-tubers, tubers, bulbs, and rhizomes are very 

Some species secrete phenols or creosoles to inhibit 
other plants (bracken, tamarisk, Juglaudaceae, Brassicas); 
others encapsulate or surround hapless competitors 

(Eucalyptus, willows, tamarisks). Some trap nematodes 
and other would-be predators, or poison them out 
(marigolds, fungi, Crotalaria ). While agricultural crops 
exploit from 0.6-4 m (2-12 feet) below the earth, some 
trees may penetrate to 50 m (164 feet) in deep desert 
sands. Around the roots of dune trees, calcium and 
other minerals are deposited as stone-like secretions by 
root-associated fungi and bacteria. Root space sharing 
is also scheduled, so that spring bulbs have fed, 
flowered, and died before the tree roots begin their 
upward thrust for nutrients and water. Tap-rooted late 
starters such as thistles and comfrey reach deep for late 
summer moisture, while a very few plants and fungi 
take advantage of the autumn rains for flowering and 

Where there is no season of cold death, as in the low 
latitudes, aerial roots may develop, or strangler figs 
send down roots from high in the crotches of other 
trees to the earth, there to build great buttresses as they 
strangle their host tree in a root well. 

For designers, the diversity of roots in soil can be 
used as effectively as the diversity of crowns and 
canopies. Unstable slopes are pegged w-ith the great 
root "tree nails" of chestnut and pine, oak and walnut. 
Even after a hundred years, the steep slopes of this 
island (Tasmania) are only just starting to collapse as 
the roots of the cleared forests rot, and could still be 
saved by pines. Acacias, or chestnuts. Bamboo not only 
holds landslides, but for light structures provides an 
earthquake-proof mattress of roots. The root mats of 
swamp vegetation save bulldozers from watery graves, 
and the fibrous web of the prairie defeats the wind. 


Many rocks and strata on earth arise from the actions 
of living organisms. Whether it is the nodules of 
manganese in oceanic depths, deposits of diatom- 
aceous earth, coal, or limestone, or opals and amber, all 
were once the products of living organisms. Much of 
the strata we see, except much-changed granitic and 
volcanic deposits, were formed from or modified by 
life. All soils are life-created, as are the corals and coral 
sands of many oceanic islands. 

Life is also busy transporting and overturning the 
soils of earth, the stones, and the minerals. The 
miles-long drifts of sea kelp that float along our coasts 
may carry hundreds of tons of volcanic boulders held 
in their roots. I have followed these streams of life over 
300 km, and seen them strand on granite beaches, 
throwing their boulders up on a 9,000 year old pile of 
basalt, all the hundreds of tons of which were carried 
there by kelp. Round stones are dredged from great 
depths in the mid-Atlantic; this does not mean that 
they were formed there, but more likely that drift kelp 
carried them there in their roots. Before they fly to 
Japan and Alaska, some millions of petrels ( Puffinus 
tenuirostris) annually fill their crop with Tasmanian 
pebbles, seeds, and charcoal, which will be voided 
somewhere in the Pacific. 


Life moderates every erosion process, every river 
basin, every cliff and rock fall. It shapes and reshapes 
earth in a thousand ways. 

The hydraulic weight of great forests, such as were 
once in the Americas, would have exceeded any water 
catchment weight we can now afford to build, and 
dispersed it over a greater area. This greatly moderates 
climate, and with it geological processes. It is possible, 
in Iran, Greece, North Africa, USA, Mexico, Pakistan, 
and Australia to see how, in our short history of life 
destruction, we have brought the hard bones of the 
earth to the surface by stripping the life skin from it for 
ephemeral uses. We can, if we persist, create a 
moon-landscape of the earth. So poor goatherds 
wander where the lake-forests stood and the forest 
deities were worshipped. The religions of resignation 
and fanaticism follow those of the nature gods, and 
man-built temples replace trees and tree spirits. 

_ 8 I 21 _ 


All of the skin and organs of the earth breathe; it is a 
regular respiration. The “diaphragm" or energy for this 
may be provided by the moon tides in water, earth, or 
air. Locally, the filling up of soil by rainwater forces an 
exhalation of air; the drying-out an inhalation. Fast 
winds disturb boundary layers, create low pressure 
and soil exhalation; slow winds and high pressures 
force inhalation. Millions of earth animals open 
breathing tubes, and arrange them (for their own sake) 
to force an exchange between the atmosphere and the 

waters, the soils, or sea-sands in which they live. Water 
is as much breathed as air. 

Deeper respirations come from deeper flows and 
fissures, and radon gas or methane seeps out from the 
earth. When the earth itself expands, great flows 
inward and outward must occur through the 
multitudinous fissures that open up in rigid sediments. 
This earth respiration transports and transforms fluids 
and their associated loads, solutes, states, and ionic 
potential from earth to atmosphere to ocean, setting up 
the potentials that create thunderstorms or hurricanes. 
We are of this same respiration. The burrows of 
spiders, gophers, and worms are to the soil what the 
alveoli of our lungs are to our body. We can assist this 
essential respiration by assisting life and natural 
processes in soils. 

If you kill off the prairie dogs, there will be no 
one to cry for rain. 

(Navajo warning) 

Amused scientists, knowing that there was no 
conceivable relationship between prairie dogs and rain, 
recommended the extermination of all burrowing 
animals in some desert areas planted to rangelands in 
the 1950's "... in order to protect the roots of the sparse 
desert grasses. Today the area (not far from 
Chilchinbito, Arizona) has become a virtual waste¬ 
land." Fierce run-off, soil compaction, and lack of fresh 
seedbed have carried the grasses away (Barre Toelken, 
in Indian Science Quest '78, Sept/Oct). 

Using prairie dog burrows as water sinks, and 
causing water run-off to flood down them, thus 
germinating stored underground seed, had the 
opposite effect on the Page ranch, now a dryland 

rehabilitation exhibit of the University of Arizona. 
Here, prairie dogs and a new and thriving patch of 
permanent bunch grasses thrive in an area where 
overgrazing, ploughing, or soil compaction has ruined 
other grasslands. 

Water under the ground has much to do with 

rain clouds. 

If you take the water from under the ground. 

land will dry up. 

(Hopi elder in Tellus, Fall '81) 

At Black Mesa, near the Four Corners area of the 
Hopi Indians (USA), a scientist studying thunder¬ 
storm occurrence (using computer analysis) noticed an 
unusual number of storms occurred in that area. She 
was told by the Hopi of the area where the earth 
breathed, emitting air as the moon affected the 
groundwater tides. This air proved to be heavily 
charged with negative ions, which may have initiated 
the thunderstorms and consequent rain. 

Of the breathing of the earth, there has been little 
study, although it was regarded as a known 
phenomena to tribespeople. The earth must breathe, by 
at least these processes: 

• The movement of burrowers in their tunnels; 

• The movement of groundwater by tides or 
replenishment of aquifers (often seen in wells, 
especially near coasts and lakes); and 

• The evaporation of moisture from soil surfaces by 
the sun. 



1 . It is a primary design strategy to prevent topsoil 
losses and to repair and rehabilitate areas of damaged 
and compacted soils. 

2. Permanent crop, soil bunds, terraces, and 
low-tillage systems all reduce soil and mineral nutrient 

3. Soil rehabilitation and pioneer green crop should 
precede other plant system establishment. 

4. Adequate soil tests, plus test strips of crop 
examined for deficiency or excess symptoms, leaf 
analysis, and livestock health should be assessed to 
guide soil treatments. 

5. If soil types can be specified, fencing, cropping, 
and treatment should coincide with these specific soil 
assemblies, and specific crop’s for such typ>e researched. 

6. Soil life processes need to be encouraged by 
provision for green crop, humus, mulch, and the root 
associates (mycorrhiza) of plants. A useful earthworm 
may need to be introduced. 

7. Drainage, hence pH and soil water capacity, need 
specific treatment or assessment, and will largely 
determine crop and tree types. 

8. Minimal use of large livestock and heavy 
machinery is to be recommended on easily-compacted 
soils, as is burning and clearing. 

9. Use pigeon and animal manure where major 
elements are scarce, as in third world areas (also use of 
greywater and sewage, or wastes). 



FIGURE 8.16 

Soil creation (A-C) and factors aiding erosion and mineral loss (D-F) 


10. Before draining waterlogged soils, recommend 
crops to suit this condition. Never drain wildlife 
habitats, fens, or bogs which are species-rich. 

11. Choose the right soil-shaping or earthworks to 
suit crop, drainage, and salt threat. 

12. Using an auger, check soils for house 
foundations. Using a (wetted) soak pit, time the 
absorption of grevwater for sewage disposal at house 

13. Preserve natural (poor) sites for their special 
species assemblies; pay most attention to human 
nutrition in home gardens, and select species to cope 
with poor soil conditions on the broadscale. 

14. Fertilise plants using foliar sprays containing 
small amounts of the key elements, or pellet seeds with 
the key elements which are deficient locally. Pelleted 
seed and foliar sprays are economical ways to add 
nutrients to plants. 

_8 1 23_ 


Cox, George W. and Michael D. Atkins, Agricultural 
Ecology: an analysis of world food production systems, W. 

H. Freeman & Co., San Francisco, 1979. 

Davidson, Sir Stanley, et. alia.. Human Nutrition and 
Dietetics. Churchill Livingston, N. Y., 1979. 

Dineley, D. etuilia.. Earth Resources; a dictionary of terms 
and concepts. Arrow Books, London, 1976. 

Fairbridge, Rhodes W. and Joanne Bouglois, The 
Encyclopaedia of Sedimentology VI, Dowden, Hutchinson 
& Ross, Stroudesberg, PA, 1978. 

Handreck, Kevin A., 

1978, Food for Plants. CSIRO Soil Division, Australia, 

# 6 . 

1978, W hat's Wrong With My Soil?, CSIRO Soil Division, 


1979, When Should I Water?, CSIRO Soil Divison, #8. 

Leeper, G.W., Introduction to Soil Science, Melbourne 
University Press (Aust.), 1982. 

McDonald, R. C. et. al., Australian Soil and Land Sun'ey 
Field Handbook, Inkata Press, Melbourne, Australia, 


McLeod, Edwin, Feed the Soil. Organic Agriculture 
Research Institute, Graton, California 95444,1982. 

Radomsky, S. W., Heidi Kass, and Norman J. Pickard, 
Elements of Chemistry, D. Van Nostrand Co. (Canada) 
Ltd, 1966. 

Satchel!, J. E. (Ed.), Earthworm Ecology, Chapman and 
Hall, London, 1984. 

van der Werf, Erik, "Sustainable Agriculture in 
South-East Ghana and The Agomeda Project" 
Permaculture Nambour Newsletter, Dec. 1985 and 
March/April 1986. P. O. Box 650, Nambour, QLD 4560 
Australia. $3.00 per newsletter. 

Weir, R. G., The Plants' Nutrient Requirements, Seed and 
Nursery Trader (Australia) July 1979, pp. 55-57,1979. 

Yeomans, P. A., Water for Every Farm, Second Back Row 
Press, Leura, Australia, 1981. 


Chapter 9 


Moving of the earth brings harms and fears 
Men reckon what It did and meant 
But trepidation of the spheres 
Though greater far. is Innocent 
(John Donne) 

And did the earth move for you? 

_ 9A _ 


Few people today muck around in earth, and when on 
international flights, I often find 1 have the only 
decently dirty fingernails. 

For the soil scientist, soil has endless classifications; 
to engineers, it is a material; to potters, their basic 
resource; and to housekeepers, footprints on the floor, 
or part of the eternal dust. However we look upon 
earth, we will all return to it, and help create the soils 
our ancestors made, ruined, or form part of. Climate, 
vegetation, animals, and soil are intimately connected, 
and each will have influences on the other. It is a great 
subject, like that of water, and this chapter will 
concentrate more on its use in structural design than on 
uses as a growing medium. 

People, and other animal species, have mined soils 
and earth deposits for specific earth resources since 
their inception; examples are animal migrations to salt 
licks, and specific dusting sites in which birds and 
mammals roll or bathe to rid themselves of parasites. 
People have used silica minerals (obsidian, chert, 
chalcedony) as tools, and have ground iron oxides or 
graphites as pigments for many thousands of years. 
Soils rich in iron oxides have long been mixed with 
acorn meals to fix the bitter tannins as insoluble ferric 
tannates ("black" breads), or to supply missing 

elements in the diet. 

There are several clays (illite, smeltite, kaolin, ferrous 
oxide "red" clays) traditionally used by tribal and 
modem peoples to absorb poisons (from Solarium spp., 
yams), to reduce diarrhoea and digestive upsets, or to 
relieve feelings of nausea (kaolin clay). Although little 
work has been carried out on this factor, we should 
record all uses when specific clays are so used, and how 
they are combined with specific food to reduce or 
eliminate poisonous or unpalatable toxins from foods. 
Some earths may be eaten to supply trace elements, as 
clay and clay-salt licks are commonly visited by deer, 
kangaroo, cattle, and antelope. Earth-eating (geophagy) 
is a widespread and seemingly natural habit of children 
and tribal peoples. As well as days, the white, 
mineral-rich ash of trees is widely used as a food dip at 
campfires by Australian Aborigines. Cooking food in 
clay is prevalent throughout the world. 

Earthworking for agriculture and monuments has 
existed for at least 17,000 years. Mineral smelting, 
pottery, and peat or coal mining for fuels increased the 
scope of earthworks, and this was quickly followed by 
the development of large machinery intended to 
remove vast amounts of ores and fuels for modern 
industry, which built quickly from 1800 on, so that the 
last 200 years of our existence has seen the greatest 
development of earthworking and mining. 

The common use of self-transporting machines really 
dates from the post-war years (1947 and on), following 
the wartime development of tracked tanks, earth 
scoops used for airfield construction, and large pneu¬ 
matic tyres for this type of equipment. While civil 
engineers have to some extent kept pace with these 
developments, neither the public at large nor those in 
architectural or agricultural fields have fully realised 
the potential of earthworking machines in the modem 

Our power to move the earth with modem machines 
is now almost unlimited; we can, if we wish, raise new 


hills or plane off existing ones, and create or obliterate 
minor landscape features. Small earthworks arc so 
immediately effective, cheap, and permanent that it 
continually amazes me that people will suffer local 
drought, seawinds, noise, erosion, or even flooding 
without spending the few hundred dollars on a 
well-built and planted earthbank that would solve the 
problem. They will build expensive tankstands or 
towers rather than a cheap hill, and suffer death by 
storm and fire rather than make a very safe earth 
shelter for their families (it serves as an outdoor cellar 
at other times). 

Earthworks are necessary and ethical where they: 

• reduce our need for energy (underground housing 
in deserts); 

• diversify our landscape for food production (fish 
culture ponds); 

• permanently rehabilitate damage (contour banks, 
interceptor banks); 

• save materials (house site design); or 

• enable better land use, or help revegetate the earth. 

As with all techniques, it profits us to make as many 

uses of earth shaping as we can; it is shameful to see 
quarries, mines and roads serving a single purpose, and 
usually left as a sterile system, when they could be 
shaped or planted to assist landscape diversity. 

A whole set of skilled and well-tried waste or soil 
reclamation strategies has developed as methods of 
stabilising devastated landscapes, both for natural 
instability and the carelessness of engineers. An 
excellent handbook for those involved in such 
painstaking work, and one covering many climates and 
areas, is that of Dr. Hugo Schiechtl (Bioengineering for 
bind Reclamation and Conservation, University of Alberta 
Press, 1980). I cannot too highly recommend this book 
for would-be earthmovers. 

Earth can be moved for productive reasons, many of 
them classifiable as landscape restitution: 

• To create shelter; to assist with foundations and to 
make areas level for floors; 

• To terrace hill slopes for stable padi crop, wet 
terraces, or gardens; 

• To raise banks or to dig ditches as defences against 
flood, fire, attack, or wandering vegetation-eaters; 

• To drain or fill areas (to direct water flow or 

• To create access roads to those places we 
commonly visit; 

• To get at earth materials (ochres, clays, minerals, 

• To make holes for any number of reasons and of 
greatly varying sizes from fence-posts to dams, wells to 
deeply drilled bores. 

• To create special storages and enlarge living space 
(cellars and caves); 

• To stop erosive forces carrying off soils (soil con¬ 
ditioning and erosion control); 

• To prevent noise pollution (embankments); and 

• To permit recharge of groundwaters (swales and 

We also move the earth to play and to plant. For all 
these reasons, we have devised hand-held and mech¬ 
anical diggers, ditchers, augers, drills, blades, buckets, 
shoes, rakes, ploughs, rippers, delvers, scoops, 
earthplanes, loaders, rock-cutters, draglines, excava¬ 
tors, and dredgers. We also move earth with explo¬ 
sives, hydraulic jets, and as an unintentional result of 
erosive processes generally. 

Erosion has itself been used to build soil terraces on 
lower slopes in more than one culture, but it is 
debatable if the terrace idea was not as a result of 
attempts to stop erosion before the idea of using erosion 
to create terraces later developed. 

Until the Second World War, earth was moved by 
sheer numbers of people, by hand or horse and car, or 
by a few people working with wheelbarrows or baskets 
over a long period. All this has changed. Why put up 
thousands of mud bricks when a machine can compact 
a 6-8 m thick wall immune to flood, fire, and 
earthquake in a few hours? Or labour long hours over a 
hole when we can blast a fence-post in a hard shale 
base for a few cents? 

In this section, 1 will not attempt to deal with large, 
complex, or precise civil works, those necessary for 
sewage layouts, the landscape excavations for large 
buildings, or large dams, ports, or aerodromes. I will 
instead limit myself to those on-farm, private, useful, 
relatively small, and rehabilitative or sustainable 
earth-moving systems that an individual might employ 
to shelter a house, or to control water in a productive 

_ 92 _ 


It is best to plan all aspects of the earth-moving process 
before the machines or labourers arrive on site. 

1. Make an initial decision where you would like to 
place the (e. g.) road, dam, house site, drains, etc., using 
a contour map and plan if necessary. 

2. Test the soil by auger holes, soil samples, and soil 
pits to determine if the soil is good enough to suit your 
plans (a good clay soil for dams is essential). Seek 
professional advice or do more research before deciding 
conclusively on placement. 

3. Peg out the site, using a level (which can be simple 
or complex), a measuring tape, and a good many stakes 
with red or white cloth attached (so that the 
earth-moving machine can follow them). 

4. Plan a place to store all the TOPSOIL removed 
during the excavations. Never allow topsoil to be mixed 
with subsoil, but carefully remove it, to be later returned 
to the site as a growing medium and to stabilise subsoil 

To stabilise the site immediately, have on hand as 
many seeds and plant materials as needed. These can 
be purchased from a nursery or grown in pots on the 
site several months before the planned earthworks (see 


9.3 Planting After Earthworks). 

When soil is moved, it becomes loose, so that soil air 
space and hence total volume may increase to 145‘ 7 < of 
the original. Even when compacted by machine, the fill 
may occupy a space 10'7, larger than the cut it came 
from. Although conscientiously compacted clay in dam 
walls may settle as little as 1% over time, loose fill will 
eventually settle to 759; or less of its uncompacted 
volume; this has great relevance to house foundations 
and wall stability. 

When topsoil is replaced over fill, the area should not 
be over-compacted, or we risk waterlogging, but when 
it is replaced over deep or solid subsoil in a cut. we will 
probably need to first rip or loosen the base subsoil to 
allow root penetration, just as we need to rip old roads, 
quarries, parking areas, or heavily-trafficked fill before 
planting trees and meadows. 

To prepare a house site (with drainage), we can pro¬ 
ceed as follows: 

• Careful survey. Place pegs outside the site. Call in 
the bulldozer. 

• Strip off topsoil carefully and mound above and at 
either end of the site 

• Cut house/garden level; use subsoil fill for access 
roads only. 

• Call in ditcher or backhoe to cut foundation and 
drainage trenches. Pour foundations and slab, paths; 
place drains and pipes. 

• Call in small blade and bucket machine (a Bobcat 
or wheeled tractor) to replace topsoil and neaten the 
site where needed. Some soil can be mounded to the 
windward side for hedges. 

• Plant or seed all topsoil to prevent erosion. 

• Fine-tune with barrow, rakes; chock drainage. 

_ 93 _ 


Every time we move soil, we should be ready to follow 
straight on with planting or seeding. That is, we need to 
have planned the planting and stabilisation of the area, 
and to have the plant materials on standby to 
implement our plan ns soon after disturbance as possible. 

There are two reasons for this: 

1. To prevent erosion, which can be severe on bare 
slopes at only 2 % slope, especially in rains; and 

2. To prevent invasion by unwanted volunteer 
plants, which may become difficult to displace later. 

If a full set of ground covers, pioneers, and long- term 
plants can be set out in new earth, a great deal of time 
and work is saved. A broadscale scatter of mixed seed, 
raked in, will prepare the way for permanent 
placements. We are most fortunate if we can im¬ 
mediately mulch bare soil sites with hay, hessian 
(burlap), or woodchips, to break the force of rain and to 
suppress unwanted weeds. 

If you have prepared for bulldozing, you have seed, 
divisions, cuttings and potted plants ready to go before 
the machine pulls out. Seed can be garden-collected or 
purchased; just scatter and if possible rake in. Some 
mixes that work in most soils: 

• Sunflower, or mixed parrot seed with sunflower, 
millets, pulses, chard, parsley, lupin, and clovers. 

• Parsnip (fresh seed), salsify, daikon radish, radish, 
turnip; all of these "spike" the soil. 

• Bulbs of lilies, grape hyacinth. 

• Roots of sunroot, comfrey, chicory, horseradish, 
ginger, sweet potato, tumeric. 

• Divisions of bamboo, banna grass, pampas grass, 
aloes, agave, New Zealand hemp. 

• Seedlings or sets of elephant garlic, asparagus, 
globe artichoke. 

• Cuttings of small fruits; elderberry, willow, poplar, 
mulberry. Pride of Madeira (Echium fastuosum). 

• Tubed seedlings of Acacia, Prosopis, tagasaste. New 
Zealand mirror plant ( Coprosma ), pines, eucalypts. 

All compete very well with self-sown weeds, and 
with very little help or none at all establish a varied and 
useful early and perennial crop system; a few annuals 
self-sow and seed down another year. Many species 
can be further divided or cuttings set out, and stakes 
can be set at the perennials so they are easily located. 
Excess grass is cut back in the following years. 

Clover can be late-sown to allow vegetable seed to 
get away. Grasses are not sown, but will invade if 
spaces appear, and can be grazed by geese in a few 
years. Failed plants can be replaced with successful 


plants late in the cycle. 

It is always an advantage to smooth-finish banks and 
surrounds so that a mower or scythe can be used until 
the selected plants take over. Trees are a danger on dam 
walls; if they fall (and they often do in those conditions) 
they take part of the wall with them, but bamboos, 
ginger, sweet potato, pcpino, and clump grasses assist 
bank stabilisation. Trees at the base of walls are 
advantageous in shading, removing water, and 
reducing weeds. 

The "net and pan" planting pattern of Figure 11.84 is 
an effective control in overgra/ed, eroded, mined or 
bulldozed sites. If tyres are available, the "pans" can be 
made from these, filled with mulch, and the diversion 
drains led in above the tread level. For people with 
access to logs, these can be staked cross-slope, on a 
slight downhill grade so that water is made to zig-zag 
across the erosion face, and hence absorb into the 

Even small logs and branches, pegged across erosion 
channels, build up a layer-cake of silt and leaves, 
beside which can be planted willow, Acacia, or any 
other fibrous-rooted and hardy species, which then act 
as a permanent silt trap. Mulch behind logs and 
barriers quickly stabilises the seed bed for planting. 
Fallen leaves and scattered dung also accumulate in 
these mini-deltas to provide plant nutrients. Small wire 
netting fences, with stone-weighted hay uphill, will 
trap silt and spread water, as will cross-swales of 
lemongrass or Vetiver grass. 

On very steep slopes, there is often no recourse other 
than to plant pampas, bamboo, lemongrass, and root- 
mat pioneers and to make upslope plantings of chest¬ 
nut, Acacia, carob, olive or other large species which 
will cascade seed downslope over time. Where 
implements such as chisel ploughs can be used, these 
are effective in erosion control. Planned chiselling and 
planting makes a permanent and stable change on 
hillside. Details on gully control in drylands and in 
tropical humid areas are given in subsequent chapters. 

_9 A _ 


Slopes are measured and expressed in several ways. 
First, the slope can be measured as DEGREES FROM 
THE HORIZONTAL, or the base angles of Figure 9.2. 

This is expressed as "a slope of 15 degrees", and is 
sometimes used by geologists to describe the dip 
(angle) of rock strata. 

Next, the 90° between horizontal and vertical can be 
divided into 100 parts, and expressed as PER¬ 
CENTAGES, a measure used by engineers. 

Finally, slope can be expressed in PROPORTIONS or 
ratios of base to height, e.g. 1:4 is a slope 1 unit high, 
with a base 4 units long. This is the rise of slope over 
distance, often used for drains and pipes, in units used 
by hydrologists. Many irrigation drains use slopes of 

(TRAVELS ( . 33-7”. S7%.) 

FXEE.-PRAN&? OAy(».2*2AS*- 


-SANPS (i:3 


The recommended proportions of slopes (or stable rest angles over a 
range of soil matenals. 

1:500 to 1:2,000, or a fall 1 m in 500 to 2,000 m, and 
these are referred to as "grades" (Figure 9.3). 

Coarse slopes are often expressed in degrees, low- 
slope drainage across slopes as a proportion ( 1 : 2 , 000 ). 
Any units serve for proportional or degree measures. 

There are suitable irrigation grades for soils and 
drains. Fine sands need very gentle drainage slope 
(1:,2000) and earth cuts in sand need an easy angle of 
rest, about 1:4.5. Table 9.1 makes clear some slope 

Stable natural foothill slopes are not straight but 
down-curved (concave). When building a road, it is 
well to remember that they will achieve a concave 
curve by slump over time, so it is best to cut this curve 


into the slope to start with. Natural lower slope laces in 
humid areas are also down-curved, and should be 
made to curve down or to be concave. Earth banks will 
assume this profile in time (indicated by a dotted line in 
Figure 9.4). Soils have type-specific resting angles with 
concave profiles. 

Slope angle (the dotted line) is therefore a 
straight-line approximation of real soil slopes. I he 
notch at the top of a cutting runs water off the face to 
safer slopes, and is a standard feature in embankment 
stabilisation. Average safe slopes used by engineers are: 

• Gravels 1:1.5 

• Clay (well-drained) 1:2 

• Clay (wet) 1:4 

To dry a road, the sun side should be cut further back 
and so allow sun in; conversely, to shade areas, banks 
can be as steep as the soil will stand (Figure 9.5). 

When we cut or "bench" into a slope, the natural 
erosion processes try to reestablish the original slope. 

Table 9.1 

SOME FEATURES OF COARSE SLOPES (given as percentages) 

100 Vertical bank; safe only in stone or very dry 
stable sediments, soft rock. 

90 Vertical bank; the walls of dry desert dugouts 
in stone can be quite stable at this slope. 

80 Precipitous. Safe only in stable rock or loess. 

70 Precipitous. Safe only in stable rock or loess. 

60 Very steep; a bulldozer can be used up or 
down, not on the traverse (cross-slope). 

50 Very steep; 1:1 proportion or 45°. Strictly not 
for tree clearing, needs permanent forest. 

40 Steep; the maximum a track machine (bull 
dozer) can safely traverse and work. 

30 Steep; as above; can be cautiously harvested 
for firewood or coppice, also benched for 

20 Moderate; usually accepted as the maximum 
slope for safe cultivation and erosion control: 
wheeled tractors are used at about 18%. The 
maximum slope of good road surfaces is ac¬ 
cepted asl3%: anything over this should be 
concreted or sealed. 

10 Moderate; may need contour banking and 
careful use. 4-6% is considered ideal for rail¬ 
roads. without special cogs or cables, to 
assist the grip of the wheels. 

0-10 Low: can erode if soils are cultivated, but 

these slopes are usually stable for crop agri¬ 
culture, terraces, and swales. 

and if left to their own devices will do so. Benching at 
the base of sloping and unstable tilted strata will 
therefore bring down the whole hill, and incur endless 
costs in road-clearing and slump removal. Slumps in 
unstable hillsides will carry with them, or bury below 
them, houses and people. 

A great many film stars perched on unstable ravine 
edges in the canyon systems of Los Angeles will, like 
the cemeteries there, eventually slide down to join their 
unfortunate fellows in the canyon floors, with mud, 
cars, and embalmed or living film stars in one glorious 
muddy mass. We should not lend our talents to creating 
such spectacular catastrophes, but to the avoidance of 
obvious problems and by re-location before disasters 
occur. Local government often delineates areas of 
instability where building is not permitted due to 
mudslides, fire, and earthquake. 

In the dry hill scrublands of California and France, or 
on desert "borders, intense fire upslope can generate 
sufficient heat to bake soils. When such fires occur in 
steep, unconsolidated shales and mudstones, the baked 
earth (heated to 6 cm deep) forms water-sealed slab 
surfaces (such hydrophobic crusts will no longer form 
crumb structure). 

Valleys in such areas can then expect catastrophic 
mud flow unless early misty rains fall to restart 
vegetative growth, and to that end the ashes can be 
sown down with oat, lupin, and shrub seeds, but if 


TABLE 9.2 



4 / B LAND ' 

c !?Y C. SLUMP 


\ 2. ROCK SLIDE \% 


/ \5 SOIL CREEP \ 



Quick clays (fine lake sediment) and quick sands may liquify 
in earthquakes and become colloids. 


heavy rains fall before plants take hold, water can 
penetrate below the glazed surface, and mass move¬ 
ment (bulking) of mud and glaze will then occur. The 
wall-of-mud effect, and the inevitable cascade 
downhill may well block roads in any such mud-flood 
emergency, threatening resources in the valleys. Mud 
flows are a feature of unstable sediments in wet-dry 

Thus, the water run-off after fire (as in Adelaide, 
Australia in 1984) can be catastrophic, and hot fires can 
have a long-term effect on soils and soil loss. The 
combination of fire in late summer, followed by a 
sudden autumn onset of rains is typical of Mediter¬ 
ranean lands, and of devastated soils. For a designer 
(and town planner) areas of known soil instability 
should be avoided as settlement sites, and kept in 
permanent forest; most are designated on soil maps, or 
can be researched. 

or gutter works by using a little water to flow down it. 
Even sophisticated instruments like the theodolite use a 
bubble level to set up the base plate, and then to check 
the telescope against this with its bubble before 
preceding with tilt or swivel measures. There are a few 
simple levels that can be handmade and are of great use 
to farmers and homeowners: 

HOSE ("BUNYIP") LEVEL. A hose level can be made 
from easily-purchased materials, and is useful to 
survey some metres or even kilometres of diversion 
drain, level a house site from corner to comer, or set a 
wall or spillway at a pre-determined level. The 
materials needed are (as put together as in Figure 9.6): 

• 20 m (65 feet) or so of clear plastic hose, diameter 
about 10 mm (1 /2 inch). 

• 2 corks or stoppers that fit into the ends of the clear 
plastic tube, each with a breather hole. 

• 2 small cork balls that freely fit inside the clear 
plastic tube below the corks (optional) 

• 2 stakes (2 m or 6.5 feet), marked with the 

measurement of your choice (centimetres or inches); 
dressmakers' tapes glued or screwed on to the stakes 


serve this purpose. 

• 4 clamps or tape to connect the clear hose to the 

Levels are taken to ensure that spillways work, drains 
run, and houses sit level enough so that one can play at 
marbles without them all falling towards one comer. 

There are tools of levelling, of which the most anci¬ 
ent and even the most reliable is that level assumed 
by the surface of water. One can always check a 
horizontal against the sea horizon, or make sure a drain 


To prepare for use, uncork one end and fill the entire 
hose with water. Be sure all the bubbles are out of the 
hose; this is only certain with a completely clear hose. 

Place both stakes together, tops level, on a piece of 
level concrete or wood. Keeping the stakes vertical, mark 
the water level in the clear tubes by unclamping and 


moving the measuring strips until the water level (or 
both cork floats) are at precisely the same measurement 
marked on the stakes. Recork the tubes. 

In the field, one person walks past the other 
alternately, driving a stake every 6 or 15 m (20 or 50 
feet) to guide diggers or machine operators, and allow¬ 
ing for the rise (or fall) of drains by allowing one cork 
ball to be an inch or so lower than the other at the next 
peg, moving the pole up or downhill to achieve this. 
The stakes must be kept vertical when measuring. 

1 cm in 5 m is 1:100 x 5 equals 1:500 fall, ample for 
most diversion drains to carry run-off to dams. Dead 
level lines can also be run across landscape, and dam 
walls checked for level or (if used for roads) a gentle 
rise. 1 recently saw a 12 km drain flowing gently all the 
way in sand at 1:2000, laid-in not by a skilled surveyor 
but by two women hired for a week and trained in 30 
minutes on a hose level. 

THE PLANE TABLE is a sturdy tripod which can 
hold a U-shaped piece of plastic tube or glass, corked 
and de-bubbled as for the hose level, except this can 
now be swivelled about to sight in all directions (Figure 

Sealed enfe> wMi swxti 
fUk ball nr pUshc buttles 

Cl«*r* h*btS 

Z f5^ual mcWc tih'cis 



Used by two people (about 15 m apart) to peg out a contour line 
around a bill. 

9.7.B). Lacking tubing, a bowl of water on which floats 
a piece of painted wood with two nails of equal length 
as "sights" will do (Figure 9.7.A). 

Although Model B is self-levelling, it may be 
necessary to tap in one nail a bit on Model A by way of 

To check a plane table, set up two marked stakes 
(with easily-visible white masking tape) a little up hill 
from the point you will stand at, driving the tops to 
level using the table. 

Viewing the stakes from position B with the plane 
table, check that the level shows new level marks (b) to 
be exactly the same distance (d) below the stake tops 
(measure this). One can then proceed to level, from 
position B, anything that can be staked, painted, or 
nicked by another person (Figure 9.8). 

This is a very handy across-valley level to set in 
siphons, or to find out where the outlet of a dam will 
send water by pipe and gravity flow, or to see if a hill 
on which you want to place a tank at a distance is 
higher than your shower head at home. 

Levelling need only be done once if done right. If in 
real doubt, buy a dumpy level or theodolite, and read 
the instructions, or if wealthy and incompetent, hire a 
surveyor (whose real job is mapping). Thousands of 
miles of drains have been surveyed, and levels set, by 
very simple tools. Plane tables of various designs are 
used by surveyors, but these usually include a telescope 
for long distance work. 

Ralph Long of Australia has devised a tractor- 
mounted level which he has successfuly used to cut 





Simple water levels can give sights across valleys or over long 


drains, using the tractor itself as a check on levels. This 
is a bubble level which can also be fitted to any vehicle 
on farms, and is called the Long Inclinometer® 
(Permaculture Journal 922, 1985). 

THE "A" FRAME. This is made from two wooden or 
metal legs, nailed or welded firmly together at the apex, 
and fixed about two-thirds down their length by a 
welded or nailed and glued cross-piece. A plumb bob 
or weight hangs from a cord at the centre of the apex, 
and a mark is made on the cross-piece at the cord line. 
The "A" frame is then reversed, and another mark 
made where the cord touches the cross-piece. The 
mid-point between the two marks is that point where 
the cord hangs when the feet of the frame are level 
(Figure 9.9). 

In use, a person swivels the frame about one leg, and 
sets in the second leg to the place where the cord hangs 
vertical. A peg is put in, temporarily, to judge where to 
place the next leg. Many metres of drain have been set 
in using A frames, often made on the spot from lumber, 
cord, and a weight for the plumb bob. 

_9 I 6_ 



It is cheaper to construct a bank than to step or retain 
the earth, if the bank can be made stable. Wherever a 
four-way bucket (Bobcat or drott) or power shovel can 
be used to dish the bank, they will remain stable at 
greater slopes than a straight cut, as we have frustrated 
soil slump by giving it the profile it would achieve had 
it slumped. Banks or cuts of more than 4 m high need 
careful stabilisation. 

Unlike dam walls, cuts for roads are not normally 
compacted, nor do they necessarily have much pressure 
on them. The greatest cause of slump is water flow 
through or over banks and the lie of strata in shaly 

FIGURE 9.12 


ground. All normal soils with some clay and stony 
banks are fairly stable, given that the angle of rest of 
these materials is preserved, the banks cut somewhat 
concave, and drainage fitted. In severe slump areas, 
re-routing of roads or expensive drainage and concrete 
retaining walls may be last resorts, but Figure 9.10 
shows the essentials of water and slump control; only 
some may be needed but all can be used. 


A bench is a flat, near-contoured cut made in a slope. 
Very severe slopes of 30-40° can be bench-cut if a 
bulldozer can start on safe ground (typically, from a 
ridge of 20° or so). Benches are used to make roads and 
house sites, and are very useful in long-term forestry if 
a steep hill is benched every 100 m or so (Figure 9.11). 
Benches greatly aid access, planting, and eventually 
harvest. The first fast-growing trees to plant are those 
on the lower (loose soil) side of the benches; these can 
be nut or fruit trees, for harvest, or for seed crop. 

Small-holders on very steep hillsides must work with 
the slopes, or expend much energy on carrying water 
and fertiliser. Orchard and mulch above poultry above 
garden is the easiest system. All the better if the ridge 
or hill above that system is planted to mulch-producing 
trees such as Casuarina and pine, oak and beech. Thus, 
mulch and bedding is thrown down-hill as greenfeed 
and seed for chickens, and they kick-down to the 
lower fence where the gardener accepts the manured 
and shredded mulch for the essential (terraced) garden 


beds (Figure 9.13). 

Benches can be fertilised, ripped, and sown to 
legumes or soft-leaved mulch plants, and periodically 
cut or grazed off. If cut, mulch can be raked to trees on 
either border. As benches on very steep slopes will 
rarely be travelled upon, they can slope slightly out¬ 
wards to drain. Benching should not necessarily 
continue across water runnels unless pipes, gabions, or 
culverts are fitted in the watercourses; small 
watercourses can be bridged. 

Benches are quickly made to a survey line pegged 
every 6 m (20 feet) or so followed by a bulldozer with 
blade set to side-cast (angled). A run with a raised 
blade will shave back or slightly step the uphill bank. In 
stable soils, benches can slope into the hill and so form 
swales to infiltrate water for trees below the bench. 
Cross-walls can be made every 20-30 m to prevent 
gutter flow. Such benches are not so much roads as tree 
shelves, and are a blessing in steep country. A quiet 
traverse with a donkey or cart serves to distribute 
plants and fertiliser (or mulch) and to gather in the 
crop. Narrow (1.5-3.0 m) benches are quickly 
over-hung by tree crop, shaded, stable, and accessible 
(Figure 9.14). 

Wherever benches cross drainage channels, pipes or 
rock-lined swales must be made to carry water across, 
and these (and their maintenance) are the greatest 
long-term expense, so they need to be well made and 

Although the true finesse of earthworks is best en¬ 
trusted to the experienced machinery driver, designers 
need to designate stages, spoil areas, topsoil stores, 
bank slopes, and so on. Also, they must remember that 
it is expensive for a bulldozer to travel far pushing a 
load before the blade to create banks (about 6-9 

machine lengths is maximum), and that much faster 
and better work can be done cross-slope and downhill 
than upslope by any machine but a bucket digger. 

Side-casting is a different matter, and graders and 
bulldozers both can bench soils effectively for miles, as 
no dirt is carried but rather cast out to one side of the 
blade, which is ANGLED to the direction of travel to do 
so. Thus, a great deal of time, fuel, money, and timber 
can be saved if a site is carefully pegged out to suit the 
machines called in. Imagine yourself as a driver, and 
make it as easy as possible to cut the shapes you want. 

On anything but a simple job, two or more machines 
may be called for, as in preparing a house site and its 
sewage lines, or in digging and carting a day deposit. 
Bulldozers can loosen and pile up material but not load 
it, bench but not trench, or at least not smaller than the 
blade width. 


Terraced lands, given a reserve of local green manures 
or composts and adequate water, are potentially very 
stable production systems. Exceptions to this arise 
when we: 

• Attempt to terrace in unstable soils or sediments; 

• Risk hydraulic pressures on hill slopes from im¬ 
pounded or infiltrated water; 

• Create terraces that are unstable at the bund or 
wall face; 

• Extend terracing as annual crop over too large a 
proportion of the landscape, and so lose leaf or tree 
nutrient input to crop; and 

• Make very large series of terraces in high rainfall 
areas, so that run-off is concentrated. 

With a useful assessment of the above factors in 

To excu/pe Animal 

To \\ou> *o\ut> 

PRAaw FOR 5oRfi*K£ 

CoxjcAve FAce. 

VOON 6vTTie* 

or coQ&e grmel so^FAce 

in BANK 
WITH Wd-e* To 

r**MM WET 40IL^?-^ 


4oi u with WAT-RcOTeP 

FIGURE 9.14 


Benches greatty assist slope access it well-drained and stabilised 

s cow/e*-T 


mind, we can gain long-term production from short 
series of polycultural terraces (wet and dry crops), 
with stable bunds (either rock-walled or at a 1:3 slope). 
Trees, on bunds and between, above, and below terrace 
series, should form 40-60% of the total landscape plan, 
and both soils and installed water inlets and outlets 
should permit safe and controllable irrigation. 

The great benefits of terraces are these: 

• Very easy crop access on slopes; 

• Easily controlled and effective irrigation pro¬ 

• Minimal soil loss due to overland water flow, or to 
slope cultivation; and 

• A potential gain in silts or nutrients in irrigation or 
run-off waters and from leaf fall. 

As with dams, terracing is most effective where 
slopes are least, as earth moved versus area of crop¬ 
land developed becomes impractical or inefficient as 
slopes steepen. At about 30° slope, but preferably at 
10-18°, terracing becomes worthwhile. 

Terrace construction always begins on the lowest 
terrace level, with the removal and stockpiling of 
topsoil over the whole area of the lower terraces, and 
proceeds uphill as each terrace is made, so that the 
topsoil of the next highest level is cleared on to the 
preceding lower terrace. Stockpiled soil at the lowest 
terrace is finally carted or lifted to the last of the series 
uphill (Figure 9.15). 

Every terrace system is ideally designed to allow 
perennial bund and terrace wall plants, specifically for 
wall stability and green manure crop. 

As for the extent and series size in a terrace system, it 
is wise to limit both on the basis of: 

• Heavy rainfall (hence expected run-off) in tropics; 

• Expected rainfall harvest in arid areas, where total 
terrace areas should not exceed one-twentieth of the 

catchment harvested, and where perennial or adapted 
crop (never water-demanding crop) should form the 
selected species. 

Thus, all terrace systems should aim to occupy no 
more than 309c of tropical or 5% of dryland areas, and 
in the tropics tree crop should be developed to maintain 
fertility of the terrace areas. Water catchment areas 
should be developed to do the same for arid areas, so 
that run-off brings leaf mulch to terraced slopes. 

In humid cool or tropical areas, wet terraces (10-20% 
of all terrace areas) can be devoted to a fish-plant 
polyculture, giving yields of fish, shellfish, and water 
plant products. Yields of protein from water cultures 
can exceed all land-based systems if managed at the 
same levels of husbandry and care. 

Wherever people occupy very steep sites (slopes of 20° 
or more), especially in areas of high rainfall, it is 
preferable to abandon broad terracing for a series of 4-6 
narrow production terraces, each series carefully 
drained to spill excess rain down permanently 
vegetated slopes (Figure 9.12). 

Thus, by ridging the terrace tips, mulching paths, and 
staggering path spills in short series, we can get the 
advantages of terrace on quite steep slopes without 
risking erosion and soil loss. Needless to say, machines 
are inappropriate for such construction, and steep slope 
terracing of this nature is always hand-cut. 



Wherever earth is dug, banks are raised. There is a great 
concentration on the holes, and far less on the mounds, 
so that "spoil" in mining becomes a pollutant. This 
need not be the case, providing topsoil is first removed 


3- 4 (*?•) 

haxwum mawr 

BBTwP&N T&mtCeS 

FIGURE 9.15 

Stable garden terraces of earth provide a total growing surtace. 


and then returned to cover the spoil, in stages or as a 
whole job. 

Just as land can be hollowed out, so roads and banks 
can be raised above marsh or flood levels, and to de¬ 
flect winds, noise, or water. Banks raised by machines 
can serve the following purposes: 

1. Shelter for houses and fields; 

2. Plant sites for windbreaks (on the crown of the 
bank and in its lee); 

3. Walls of houses or storage bams; 

4. Containments for large inflammable fluids, and 

5. Noise deflectors and absorbers, e. g. at airports 
and along highways; 

6. Tracks and plant sites in marshes and on clay soils 
subject to flooding; 

7. Patterns to deflect and direct wind and water to 
storages or energy systems; 

8. Rood or tide control systems (polders and levees); 

9. Railways and road grade adjustment; 

10. Earth ramps and stands; and 

11. Earth walls or "ha ha" fences. 

These are further elaborated as below: 

flatlands or on high exposed sites, an earth crescent 
bowed into the cold winds is the fastest way to create 
shelter and warmth on its lee side. Even a few blade 
sidecasts run along a field boundary provides cover for 
hedgerow and windbreak species and may act as a 

swale for root water collection. High banks of 2.5-3.5 m 
(9-12 feet) close behind house sites, whether excavated 
or raised, create instant shelter over the occupied site, 
shelter which may be further reinforced with trees 
(Figure 9.16). 

This is a long term and considerable heat energy 
saving in cold climates, and a shading or cooling wind 
director in warm climates. Figure 9.17 shows an actual 
ground design for a flatland site with cold southwest, 
hot northwest, and cooling northeast winds, all 
controlled by one earthbank and the pond formed by 
the excavation. 

casts heap up topsoil, create shelter, and catch or delay 
run-off, as well as reduce root competition for a year or 
two, all good reasons to sidecast for long windbreak 
sequences, and in wetter ground to establish willows, 
poplars, and tamarisk above water-logged ground 
(Figure 9.18). 

3. HOUSE OR BARN WALLS. Unrealised by most 
architects and home builders, machines exist which can 
raise and compact a complete house or bam wall in a 
morning's work. All we need to add is floor and roof 
(another two days work) to be in a long-term, fireproof, 
silent, energy-conserving and sheltered house. This 
technique is suited to open-space situations, cheap 
bams and large outbuildings. As the walls are raised, a 
smaller tractor and roller can compact them. Almost 
any earth will do, providing the compacted rest angle is 
watched. This technique is not suited to sands unless 
wall corners are bagged (stabilised with soaked bags 


FIGURE 9.18 


shelter, flood-proofing, fire-proofing, noise reduction, and drainage 


filled with cement and sand or sandy soil). Figure 9.19. 

4. CONTAINMENTS. Whether for inflammable 
fluids or as fire-proofing, and especially effective 
against radiant heat, earth walls can surround tanks. 
Above-ground wildfire radiation refuges in bushland 
are earth-covered and may be built off forested roads 
and near isolated bush houses. 

noises are effectively blocked from housing by earth 
walls, and plants on these banks decrease noxious fume 
effects. Deflection of noise is effective for long wave¬ 
length noise only. 

Earthbanks, islands, and mounds in marshes give 
multiple opportunities to access and place trees and 
structures. Mounds in ponds isolate useful but ram- 
pagious species such as thorny blackberries and runner 
bamboo, while banks allow foot or vehicle access across 
and into marshes to place and service duck nest boxes, 
to harvest fruit and vine, and to attend to fish ponds 
(Figure 9.20). 

The raising of a bank in marsh is an interesting 
operation; the best tool is a very light "swamp" tractor 
with wide tyres or tracks, and a swivel bucket (an 
excavator). This unit, perhaps using "mats" in very soft 
or silty ground, can dig and raise an earth bank where 
the ground is too soft for the operator to walk. 
Equipment can be light for the first crossing, the aim 




FIGURE 9.21 


Walls or trenches on hilltops ’steer wind to mills and are durable 


being mostly to throw up a broad earth mound to dry 
out, so that a safe transit of heavier equipment can be 
made at a later date and a substantial bank raised for a 
road-bed or planting. It is easier, of course, and less 
harmful, to first raise banks, and then create a marsh by 
building a low berm. Natural marshes need protection 
for their unique values and for waterfowl. 

"Mats" are three bulky wooden gratings, made of 10 
cm by 15 cm (4 inch x 6 inch) timbers, which the bucket 
machine stands on. At each move the machine itself 
recovers one from behind and places it ahead. Once the 
first mound is built, larger excavator machines can 
reach out to dig deep channels and build high banks of 
great solidity, or the smaller mound can be levelled by 
light tractor for foot traffic. Draglines are not really an 
alternative in mound-building, and in timbered 
swamps are impractical. 

illustrates a design based on older Afghan mills of a 
saddle or ridge wind tunnel for mill power. Systems 
for water diversion are discussed in Chapter 11. 

8. FLOOD AND TIDE CONTROL (polders and 
levees). Well-maintained earth banks are the only 
protection of houses and villages in flood plains and 
below tide level. They are, in effect, reverse dams, the 
inhabitants living inside and the waters contained 
outside. Mounds can be built as flood refuge islands in 
many deltaic areas, containing storage barns and 
refuges in fields subject to periodic flooding, dangerous 
to people or animals. Causeways of earth are often used 
to access low mounds or islands near shore. Bangladesh 
and other deltaic areas need wooded refuge mounds 
just for the survival of people. 

Such mounds can also be made in fire-prone sites, 
where villages and houses are safe in lakes or on 
moated islands. Peninsulas should be included in dam 

construction for this purpose by designers (Figure 9.22). 

common banks and cuttings are all well-known to all of 

10. EARTH RAMPS AND STANDS. Earth ramps and 
stands are of great use for at least these reasons: 

• To unload trucks from the side or back (heavy 

objects and wheeled vehicles); 

• To load cattle to trucks, at various levels; 

• To unload hay or bales into the upper floors of a 

bam for use at lower levels; and 

• To load and unload boats into water. 

Once built, they are permanent in use, and sometimes 
a whole district can use the facilities of one loading¬ 
unloading ramp. The loading face itself must be 
stabilised with stone, concrete, or beams (Figure 9.23). 

ha" is a below-grade ditch, which acts as a fence. It is 
used in classical vista gardens where views are to be 
uninterrupted, and in zoos for direct viewing of large 
and potentially dangerous animals. It is also a defence 
for villagers against stock where the resources do not 
allow wire fences, but labour or a machine can be 
obtained. It is essentially a deep pit, dry or wet, with 
one steep wall faced by stone (Figure 9.24). It can be 
scaled to size for the species excluded. 

The same machines that build roads will also build 
wetlands, swales, and small dams suited to wildfire 
control and wildlife. Underpasses and guide fences 
allow migrating wildlife to cross road and rail ways 
without accidents. 

Roadsides can be an area for the preservation of 
bunchgrasses, sagebrushes, rangeland and meadow 
plants, and remnant forests along their way, with 
pull-over areas and vegetation maps, geological 
features, and archaeological or fossil remains clearly 


indicated. Such planning must precede actual con¬ 

We pour kilometres of black bitumen surface, but fail 
to lay under it pipes for heat pumps that would heat 
the towns through which the road passes, and we fail to 
harvest and store road run-off for local irrigation and 
wetlands. All this will change only when well- 

intentioned people govern the spending of public 
monies, or when road engineers are trained in perma- 
culture, and look upon roads as a community resource! 

O Q 


Just as there are hand tools suited to particular ways of 

FIGURE 9.24 

Much used in areas where post and wire fencing is unavailable or 

FIGURE 9.23 


Cheap and permanent ramps ensure easier load and unload 



Down among the dead men 
Let me lie.... etc. 

However, the exigencies of education have meant 
that designers and architects have seldom been 
personally involved in earth moving. A brief 
description and nomenclature of machinery and 
modem tools is not only needed but essential to earth 
design, given that when we move earth we should do 
so for permanent and beneficial ends. We can 
revolutionise eroded and arid landscapes by 
commencing the process with tools and consolidating it 
with life forms, especially trees. 


People have always moved earth: to reach water in dry 
river beds, to mine pigments for their decoration, to 
excavate food as bulbs, grubs, or fungi, and to bury 
their faeces or their dead. The archetypal tool is the 
digging stick, which gets food of greater variety and 
more nutrition than the spear. The basic hoe, rake, and 
shovel exist today in most cultures. 

Hand tools have moved most of the earth we see 
today shaped into mountain rice terraces. There are 
some very useful and cooperative ways to dig, effective 
in making miles of low irrigation banks or unloading 
gravels. The two-person shovel is useful here, one 
digging in, the other pulling over in a see-saw motion 
(Figure 9.26). Try it, and be surprised at how rhythm 
and cooperation will move mountains. Sing a little tune 
to pass the time and get the rhythm: 


Reserve Jx? 

FIGURE 9.25 


Biological planners can make many productive accessories lo 

roadways; roads can provide energy benefits and conservation 



digging, so there are large machines suited to special 
landscape tasks. Any of these can be supplanted by 
human labour where it is plentiful. The basic 
earth-moving attachments are these: 

• BLADE (can be mounted on almost any vehicle, or 
towed); includes "V" blades or del vers. 

• BUCKET (for lifting and loading loose material); 
narrow and toothed for hard ground, or of special 
shapes for drains. 

• BUCKET CHAIN (for foundations, pipelines, 
narrow deep ditches, underwater dredging). 

• SCOOP (can be horse or bullock-drawn, or 
articulated on an hydraulic or telescopic arm). 

• RIPPER (for breaking up compacted soils); usually 
towed or rear-mounted on tractors. 

• DELVER (for one-pass drains; often mounted on a 
grader, or towed on a frame behind a bulldozer). 

• SPINNER (rear-mounted on a special tractor); a 
fast-revolving disc of about 2-3 m diameter with 
peripheral buckets. 

• BORERS AND DRILLS (holes, fences, explosives, 
pipes, wells, bores, and the like) 

• JET PUMPS (to pump out silt and sand in wet 

As well as these, there are explosives, which are of 
special use in marshes and swamps, and some special¬ 
ised tools for rock and swamp work, for mines, and for 
massive tunnelling. 

Our concern here, however, is for the common tools 
of landscaping and water storage or water channeling. 
Each has appropriate uses, although most can do 
something of what the others do. To take them one at a 

The Blade Machine s 

The blade earthmovers are the machines for levelling 
and benching or terracing, and ideally they should be 
able to lift (and drop), angle, and tilt. They can be 
mounted forward (bulldozer), in the centre (grader) or 
at the rear (wheel tractors, for levelling). Tilted, the 
blade can make shallow V ditches, or put crowns on 
roads. Angled, it spills earth to one side as steering 
walls, or makes long shallow drains. 

Blades are ideal for levelling house sites, for terraces, 
for benches on hillside, for side-cutting roads, and for 
pushing up earth walls. Even a small tractor (17-25 
h.p.), patiently worked, can make very large dams and 
terraces at less fuel cost (but greater time cost) than a 
bulldozer, while large bulldozers are the most 
economical of time. They can work difficult, steep, or 
stony sites and move very large objects such as 

The bulldozer is a blade machine, mainly for pushing 
and planing earth. It is of greatest use in reading and 
for dams. It is an excellent machine to put up, roll solid, 
and spread earth, to dig large shallow holes, move 
small hills, and bench. The blade TILTS for road crown 
slopes and ANGLES for casting aside windrows of 
earth; it also LIFTS to spread and release loads, and 
DROPS to delve out drains and ditches. 

Angled blades are used in long runs to cast earth out 
continuously to one side (called side-casting). Tilted 
blades are used to cut channels or to bench slopes, and 
lift is used mainly for piling up or levelling loads. 
Blades are normally forward-mounted for sight and 
control reasons, but on that special road machine, the 
GRADER, the blade is mid-mounted to give even 
spreading, and on small farm or wheeled tractors are 
often rear-mounted. Some small blades rotate about 
their axis (180° swivel). The grader can be used to make 
long drains, of shallow angle; these are miscalled spoon 
drains, but are effectively more angled than spooned in 

Thus, for all normal bench work, a bulldozer is 
useful, and for long flat road or levelling runs a grader 
is better. A SCRAPER is a large, self-filling bucket or 
land dredge which can both fill and empty itself to 
plane off or dig out large areas. All large machines can 
now be laser-guided to accurately level and grade 
fields at a pre-set slope. Lasers can also automatically 
work the hydraulics to lift and drop earth, but land 
forming is mainly restricted to large flattish irrigation 
areas or civil works, and is normally contracted out to 
specialists with large machines. 

The Four-Wav Bucket 

This machine (sometimes called a drott) combines all 
four motions of lift, dig, push, and pull, and is a 


I'.*71» * 113 * 117 -* 


FIGURE 9.27 


On many machines. lilt, angle, and lift blades enable accurate work on 
roads and drains. A selection ot blades and systems are shown A * 
grader. B • delver. C - spinner, D • bulldozer. 



bridging and universal machine between blade and 
bucket types. It is usually fitted to a bulldozer body, 
and is an excellent landscaping machine. It differs from 
some bucket machines in that it cannot swivel the blade 
separately from the body of the machine, nor can any of 
the above blade machines. It is sometimes called a 
clamshell bucket because it can close on loads of earth, 
or delicately pick up large stones, shave a curve in 
embankments, or fill a truck with soil. 

A small wheeled machine, the Bobcat, is an excellent 
finishing tool or used alone for light work or for 
making swales in Zones 2 and 3. 


These can be simple and fixed or complex and 
swivelled; the former are often fitted to wheeled 
tractors as LOADING BUCKETS of great use in 
quarries, nurseries, and anywhere loose material needs 
to be picked up and loaded to trucks at heights up to 4 
m. They can lift and tip. but not swivel sideways. 

A very useful tool for drains, and as a tool in 
marshes, is the SWIVEL or SCOOP BUCKET machines, 
which can scoop out, swivel around, and deposit loads. 
Some of these machines can dig wells to 9 m (30 feet) 
using hydraulic extension arms, and all can dig 
sharp-edged pits or drains for special uses. They can 
normally reach out 6-10 m (20-32 feet), and (standing 
on dry land) take silt from canals or ponds. To reach out 
much further, there are two tools, the DRAGLINE, a 
giant fishing rod or crane which casts out a loose or 
tractor-tethered bucket dredge up to 18 to 24 m (60 to 
80 feet) and hauls it in full, and a two-tractor dragline, 
where one tractor hauls an endless rope with a bucket 
across greater distances than the crane dragline. 

SCOOPS are often used behind horses or oxen to 
excavate small ponds or clean out ponds of silt. Unless 
fitted with a rear spill-door or chain tipper, they are 
very hard work to tip by hand alone, and tire one out 

A special tool of great efficiency in flatlands and on 
low slopes is the SPINNER, a large wheel with small 
peripheral buckets spun at high speed, which throw out 
the earth as small clods a considerable distance. They 
are much used in Holland to drain polders, and are the 
most economical and speedy machines for flatland 
(shallow-) drains. The spinner is one tool that distributes 
the spoil as small clods as it travels; there are therefore 
no banks beside spinner drains. 

A special TRENCH DIGGER is a chain-bucket sys¬ 
tem which continuously digs narrow trenches for 
pipe-laying or to insulate foundations. Commercially, it 
is called a “Ditch-Witch®" or 'Trench-Wench®". 

These are hand or mechanical post-hole diggers suited 
to most soils. Other uses are in tree and tuber planting, 
although care must be taken not to compact soils or to 
create water-filled holes in clay. The prime use is for 
posts and fencing at present. Augers have a limited lift 
and are used to (normally) 2 m (6 feet) or so depth. 

whereas drills w hich have extension tubes can operate 
to great depths. The borings are removed bv liquid 
flushing or are simply compacted and tube-lined. 
Purely hydraulic drills work to great depths, and bores 
and hydraulic nozzles arc often combined. 

Some of the largest vertical and horizontal earth holes 
(mines and quanats) were once hand-cut by primitive 
tools, and wells to 30 or even 60 m (100-200 feet) are 
still hand dug throughout the world. Special large-bore 


augers to 1 m (3 feet) are used at mines, and most carry 
extensions to make a 2 m wide shaft. Very large 
pneumatic blowers are crane-mounted to remove loose 
materials, and are often locally made as at the Coober 
Pedy opal mines in Australia. Large-bore drills there 
are called Caldwells after the inventor and are used for 
underground housing, excavation, shafts, and tunnels 
up to 1.5 m (5 feet) diameter. 


Explosives are of most use to assist auger holes in hard 
ground, to make holes in otherwise unstable ground 
such as marshes, or to loosen rock in quarries. With the 
advent of the swamp tractor, marsh blasting is less 
common, but the basic ease and effectiveness of 
explosives should not be overlooked where they can 
solve some otherwise intractable problems. 

Nitroglycerine (cellulose treated with acid, in 
glycerine, absorbed into wood dust or clay earths) as 
gelignite, dynamite, or plastique is an inexpensive way 
to solve some earth-moving problems. Even cheaper is 
the mix of ammonium nitrate fertiliser and dieseline 
known in the trade as "chickenshit" (nitrates have from 
ancient times been gathered from manures, around the 
soil of toilet pits, or extracted by washing and 
evaporation from guano). 

Old "recipe" books give dozens of reliable recipes for 
cheap explosives, and even custard powder, flour, or 
face-powder will blow a room apart, as will the fumes 
from ether or domestic gases. I once worked as a 
scientific glassblower, and managed to remove all doors 
and windows from my room by allowing ether to 
evaporate from a bottle. Earlier, as a baker in my 
father's business, I created some spectacular flashes 
using plain flour near open flames. 

Today, we must take a course to obtain a “powder 
monkey" certificate in order to set our own explosives, 
or we should hire skilled people. Yesterday (pre¬ 
terrorist), we simply made the stuff up and let it go, 
with unpredictable results and often too much effect. 

Hydraulic lets 

There are several ways in which the quiet but powerful 
action of water jets assist our endeavours. Firstly, a 
simple jet nozzle fixed inside a pipe and connected to a 
garden tap may well serve to drill a water bore (a water 
spear) in a few minutes or hours in sands, gravels, or 
deep soils. Secondly, an old hose-pipe fastened to a 
sharpened pile or post and connected to a hose will 
serve to sink jetty pilings in silt or sand in very little 

A jet pump (commercially available) will remove silt, 
sediment, mulch, and even large gravel from a dam, 
and deposit these behind a retaining wall as rich terrace 
soil, while the water flows back to the dam. Lastly, jets 
fired at loose sediment washes down gravels, sands, 
and soils for mining, as terraces, or to remove land slips 
from roads and fields. Quite precise control of such 
action is achievable. 

Hydraulic nozzles, "drills", and jet pumps are all 

made by industry to serve these purposes, and also to 
steer deep drills in boreholes to specific locations 
underground when tapping oil, thermal energy, or for 
venting mines and caves. Again (as with explosives) it 
is enough to know the range of uses, keep them in 
mind, and to get good advice if the need arises. 
Inadvertent jet drilling has a powerful pulling action, 
and jet pumps with their motors, rafts, or platforms can 
be dragged below water or across the ground if one is 
left unattended. Occasionally, a garden hose will bury 
itself in sandy soils in this way and so be lost. 

Powerful air jets now take gravels from mines in 
much the same way. and a whole series of turbines and 
powerful pistons operate from pressure applied by 
water, air, or oil (the science is applied hydraulics, or 
pneumatics). A jet plus a cutting drill will cool the area 
and remove waste, in one operation. 


Rakes and rollers are the tools for finishing excavated 
earth; the former to fine level, the latter to compact. 
Compaction is only necessary where traffic or water 
retention is intended, but where it is necessary may 
need to be accompanied by water sprinkling in dry 
conditions. Care must be taken to compact only 15-30 
cm (6-12 inches) of soil thoroughly at a time. Even very 
heavy machines can seldom compact depths greater 
than 38 cm (15 inches), and impact or hand compaction 
is effective for less than half that depth. It is necessary 
to strictly adhere to this careful compaction for dams 
and house foundations. Modern compacting machines 
often vibrate, using a pneumatic or mechanical 
eccentric weight to impact and shake soil as it is 

_ 9 .9 _ 


Whenever earth is moved, it seldom reveals a uniform 
composition; in fact, most excavation reveals materials 
already sorted by nature, and of specific use. To mix 
them up is to set back the clock a few thousand years, 
and the supervising designer or property owner will do 
well to follow every excavator (animal or technological) 
and put aside the following: 

TOPSOIL. Topsoil is the often dark, root-filled living 
surface of the earth. It is to be carefully stripped off, 
piled aside, and later returned over other material onto 
banks, over padi or fields, and even below water in 
ponds. Topsoil can be very thin and rare, and is usually 
no more than 6-18 cm deep. Where deeper, it can be 
spread on poorer soils to help them produce, or 
pocketed for trees in poor soil areas. 

PEATS. Excavation in marshes, bogs, or lowlands 
may reveal 1-9 m (3-30 feet) of semi-compacted fibrous 
plant material. Most can be stockpiled, otherwise 0.6 m 
(2 feet) or so returned to the surface as for topsoil. The 
peat stockpile is most valuable for mixing with sands 


and loams for making even more topsoil. It can also be 
used as a fine growing medium in nurseries, as an 
insulator in buildings, and only in desperation as a fuel, 
for those who burn peat are near the base of life on 
earth; the next step is into barrens and rocks. Peatlands 
throughout the world now urgently need preservation 
as threatened habitats of unique vegetation. 

Peat preserves timber, animals, and such unexpected 
treasure-troves as hoards of acorns and firkins of beech 
butter from the forests which preceded the bogs. A 
whole archaeology may very well lie in peat, and the 
pollen record may reveal past history. At the base of 
Irish bogs the Fir Bolg (the little people), their axes, 
bridges, butter, and forest life are well preserved. They 
and their forests were banished, as if by magic, by the 
Tualha tie Damn (the Children of Diana) who now dig 
the peat. Diana was displaced in turn by Mary, mother 
of God. But all are mixed in the peat and the tongue of 

CLAY. Good clay is very useful stuff; a depth of it can 
extend 0.3-6 m (1-20 feet). This resource can be 
stockpiled, and preferably covered with plastic sheets. 
Both dried and baked brick can be made of it, dams and 
ponds sealed, and pots shaped and fired. Some types of 
clay make good cricket pitches, and other types make 
fine porcelain or special filters and insulators. Fireclay 
is 58-75% silica, 25-36% alumina, 0.25-2% iron oxide; 
silica bricks 95% silica, no alumina, and <2% of lime. 

SAND. Clean, it may make grinding powder or silica 
chips, or if yellowish have enough calcium to counter 
acidity. If fine and black, it may be of use in casting 
metals or as a material for a black-sand solar collector. 
If white, it reflects light like snow and can reflect heat to 
houses and walls. Fat sand (containing some clay <20%) 
makes ovens and mortar; sharp sand (or mostly silica) 
makes glass and cement, or can be mixed with peat to 
grow trees or other plants in nurseries (the best use). 
Sieved sand gives special sizes for special use as a grit 
or polish in mortars and grinders. 

GRAVELS. Heaped up, it makes good roads, drains, 
and soft sun-bathing patches much better than lawns 
(no green stains). Angular, gravel makes good concrete, 
and smooth, good water filters or enzyme columns. It is 
a mulch for trees, as is cinder and crushed pumice. 19 
mm-size angular gravels are the best for heat stores, 
where air from solar attics or glasshouses is blown into 
a heat store wall or tank filled with such gravels. Heat 
stoves can be placed under floors to heat gravel beds. 

SHINGLE. Shingle is good under gravels on roads, 
for drains, and coarse filters. It is an excellent mulch for 
condensing water in deserts or dry places, a refuge for 
snails and decomposers, a filter bed for swimming 
pools an naturel, and so on. 

SLATE. Floors, tablets, and billiard tables are of slate, 
as are roofs. Any rock that can be split can be utilised 
for walls and houses, roof areas, garden paths, and 
floor tiles. 

BOULDER. Boulders can be used as a coarse mulch, 
wildlife refuge, and walling and windbreak material 
which gains and radiates heat. Some boulders are very 

good as pounders, others excellent mortar and pestles, 
weights, anchors, and ballast in boats. 

To me at least, a bulldozer or excavator is a source of 
information, and the making of a pond is a rare chance 
to explore, explain, and store useful information and 
material relating to the site. On a complex site (old 
volcano, shoreline, swamp, or desert pediment), one 
can confirm or deny theories on formation, geology, 
and geological history. Best of all. experience on many 
sites gives a predictive capacity on similar sites, and 
more confidence in finding the right sites for ponds, 
excavated houses, silos or silage pits, and in finding 
more earth resources. All this, and just for a careful look 
at actual operation. It would not be uncommon for 
excavation to pay for itself on any one of the factors 
listed, and for yourself or your client to benefit long 
after the water storage is built, from materials put 
carefully aside during excavation. If you are wise, you 
never leave the site when earth is being moved; it is very 
expensive to bring machines back for fine touches, to 
adjust the work, or to sort out mixed materials. 


Like the snow and windblown sand, newly moved 
earth and puddled clays reveal to the observer a section 
of earth life, and makes an imprint of those secretive 
and nocturnal birds and mammals on site, from beetles 
to elephants, mice to plovers. After rain, it is a good 
time to take a notebook and observe the footprints, 
scrapes, and tracks of any site where earth was freshly 
moved. A list of species obtained this way adds to basic 
information resources and may warn of troubles in 
store from ground foragers. Many cryptic animals 
avoid traps, but can be detected by their tracks. 

The earth hides a great variety of life forms, from 
secretive larvae and worm-like legless lizards to 
redolent fungi revealed only on the surface by their 
garlic-like scent or fruiting bodies. Mice, gophers, and 
larger mammals leave tunnels, nests, and food stores 
underground, and all these and other secrets, such as 
the extent of root penetration and spread, can be re¬ 
vealed for our analysis. 


Under the earth, almost everywhere, lie the mute 
stories of prior life. These have more lessons for us than 
do futurologists, who after all can only look forward by 
looking back first (or they would not know which way 
is forward). The camps of our ancestors are revealed in 
soils by shells, tools, shards, ashes, bones (and can be so 
dated). Buried trees give growth rings to tell the story 
of older climate, air quality, and to accurately date their 
own burial. Pottery shards may encode astronomical or 
technological data, and bones reveal past diseases and 
wars. As the Ganges River today bears its children's 
bodies, their clothes, adornments, and possessions to 
sea, to race blindly over the continental shelf to the ooze 
below, and as we carelessly drop broken pottery on the 


ground, so in the far future other people (or other 
minds) may want to know about us, how we lived and 
perhaps when and why we died. Today's disposal pits 
may well become tomorrow's mines. They are 
ourselves in past cycles, an expression of life preserved 

_ 9A0 _ 


Bradshaw, A.D. and M.J. Chadwick, The Restoration of 
Land, University of California Press, 1980. 

for our education and guidance. 

SchiechtI, Hugo, Bioengineering for Land Reclamation and 
Conservation, University of Alberta Press, 1980. 


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Chapter 10 




The subsets of climatic zones included in this chapter 
specifically exclude arid tropics, which are included in 
Chapter 11, together with cold arid areas. As plants and 
techniques do not split off neatly into climatic areas, the 
following three chapters should be read in total for any 
one site. A subtropical site, for instance, can have quite 
severe frosts, cold winds, torrential summer rains, and 
7-9 months of drought, so that it needs the strategies, 
earthworks, and species suited to temperate, arid, and 
tropical humid climatic regimes. However, it is true that 
soils and climatic characteristics do dictate the specific 
broad design responses. 

Some special topics of the humid tropics are those of 
soils, mulch sources, planning for polycultures, and 
appropriate house construction, each of which is given 
a section. 

In the wet tropics, heat and high rainfall would leach 
most mobile nutrients from soils, except for the biomass 
of the great variety of plants, which contain 80-907, of 
the available nutrients. Humus is an essential soil 
fraction, and humus creation must be given 
considerable emphasis as prerequisite to sustainability. 

Inappropriate strategies are those of bare-soil 
cultivation, or intensive clearing and burning in short 
cycles (less than 8 years or so) for cropping. Appropri¬ 
ate strategies involve complex and multi-storied plant 
systems designed to yield basic staples, create mulch, 
and preserve soil nutrients. 

James Fox in Hanv*t of the Palm (1977), has been one 
of the few who have analysed the social changes and 
loss of self-reliance following the abandonment of 
ancient and balanced palm polycultures in Indonesia. 
Ancient tropical civilisations have been noted for their 
stability, indicating that sustainable land use patterns 
are an essential prerequisite for social harmony. 

The Food and Agriculture Organization of the United 

Nations (FAO) admits to failure in transferring 
mechanised monocultural sustems (barely sustainable 
in temperate moist areas) to fragile African or tropical 
soils. It is a wonder that this was tried at all in modern 
times; the clearing and cultivation of tropical soils has 
for decades proved disastrous, and most ecologists 
would have predicted this failure by the early 1930‘s. 

Complex perennial fodder and food systems are 
known to be stable, but are not as yet part of the 
officially funded agricultures from such sources as the 
World Bank. Deserts present even more fragile systems 
and need greater skills to stabilise and manage. The 
most inappropriate advisor is an agriculturalist trained 
in "modem" techniques. What is needed is continuous, 
local education of experienced people and a lateral 
transfer of their evolved skills. Emphasis in such 
education should range from an analysis of health and 
environmental problems to practical solutions, with 
sophisticated plant/animal/technological assemblies 
adapted to local food preferences, nutritional needs, 
and cultural requirements. 

Romantic literature on the "easy' tropical life leaves 
out the skin cancers, rodent ulcers, dengue fever, filaria, 
malaria, chronic bowel and skin disease, and the 
constant battle with rampant growth that is an 
everyday experience at Latitudes 0-25°. That, and the 
pythons, ticks, termites, rain, mould, and lethargy 
caused by heat exhaustion. With the increasing loss of 
atmospheric ozone, it is folly for fair or red-haired 
Europeans to expose bare skin to the tropical sun—a 
cause of skin cancer in Australia and "haole rot'' (a form 
of fungal bleaching of the skin) in Hawaii. 

Humid heat induces a lethargy compounded by 
chronic illness in many populations. Water-borne and 
mosquito-transmitted diseases are almost impossible to 
totally control, given the aerial resevoirs of water 
developed by palms and bromeliads. In houses, 
induced cross-ventilation and careful construction for 
mosquito control are essentials, as are plant systems 



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iS*€&7 P^OTo, prc 

based on a tree-species polyculture; the two combine 
very well to reduce climatic extremes. 

We can largely emulate the tropical forests them¬ 
selves in our garden systems, establishing a dominant 
series of legumes, palms and useful trees with a com¬ 
plex understory and ground layer of useful herbaceous 
and leguminous food and fodder plants; vines and ep¬ 
iphytes can complex this situation as it evolves. In the 
wet-dry tropics, more open palm polycultures are 
appropriate; the excesses of heat, light and rain are best 
modified by an open canopy of palm fronds and the 
fem-like leaves of tree legumes. 



(Based on Trewartha, 1954) 


These are the river basins and wet coasts from Lati¬ 
tudes 0-25°. Major localities are the Amazon and Congo 
basins. Central America, Sri Lanka, Malaya, Borneo 
coasts, and New Guinea. This climate covers about 10% 
of the earth's surface (5% of the human population). It 
is heavily occupied only where terraced alkaline 
volcanic soils enable sustained cultivation (Java). It 
contains remnant tribes of hunter-gatherers (often 
pygmoid) in remaining forests, and is rapidly being 
ruined by over-exploitation of forests, mining and 
extensive cattle rearing, mostly developed by large 
corporations. Hence, there is a recent tendency for 
catastrophic wildfires to develop in logged areas such 
as Borneo, and for soils to be leached to low fertility, or 
eroded to ferricrete or silcrete subsoils. 

The sun is mostly overhead, with temperature fluc¬ 
tuating little at about 21-32°C (70-90°l : ). Humidity is 

A-6-C •' Zones of direA -swligkt. 

P: Zone, cf reffecM or UM. 

e: tot-zke. ° 

FIGURE 10.1 

Dense planting is possible, and beneficial near villages; species 
assemblies are simplified on the broadscale Levels in natural forests 
are also indicated (after Moore. New Scientist, 21/8/86) 


constantly high, frost unknown. Rainfall is from 
152-328 cm (60-129 inches), with rain most days and 
frequent thunderstorms (75 to 150/year), usually 
towards evening or late afternoon. 

The landscape features perennial streams, deeply 
weathered and rotten rock over bedrock (regolith), and 
rounded hills. There is rapid water run-off and 
evaporation, with swamps confined to coasts and 
lowlands. Rivers usually have flood-plains and 
extensive alluvial plains and deltaic deposits. Access 
inland is often by rivers and tributaries. 

The vegetation is luxurious, best developed as 
broadleaf rainforest with lianas and epiphytes, very 
much mixed as to species—up to 800 tree species per 
square kilometre. The shaded floor of the forest con¬ 
tains little growth and has subdued light. Mangroves 
are extensive on appropriate coastal and estuarine sites. 
Growth is rapid, uninterrupted and continuous. Insects 
and birds are plentiful and varied. Most fauna is 
nocturnal and arboreal, and there are abundant fish and 
aquatic species. Ground grazers are rare and large herd 
species do not occur. 

About 85% of nutrients are held in plants or animals, 
so the soils themselves are infertile especially if 
clear-cultivated, tending to erode and leach to insoluble 
oxides of iron and aluminium. Only terraces, 
flood-plains and new volcanos keep some soil fertility 
replenished or held if land is cultivated. 

Staple cultivated foods are plantain and banana, 
cassava, yams, coconut, corn, taro, paddy rice, ducks, 
pigs, poultry, and fish. Trade and plantation crops are 
spices, copra, palm oil, cacao, rubber, banana, manilla 
hemp, rare hardwoods, balsa, tropical nuts, chicle, and 
drug plants. 

Housing is usually raised, steep roofed, thatched, 
with permeable walls, and screened. Health problems 
relate to sewage disposal, insect vectors, and skin fungi. 

Design essentials are for: 

• Hygenic faeces disposal. 

• Clean water sources. 

• Integrated and benign insect control techniques. 

• Gradual replacement of ground crops by trees. 

• Preservation of natural stands of trees. 

• Development of river versus road traffic. 

• Evolution of natural products . 

• No-dig (mulch) techniques on root crops. 

• Domestic foragers for snail and insect pests. 

• Appropriate medicinal plants. 


These adjoin the wet tropics but are poleward of them. 
They take up about 15% of earth's surface from Lati¬ 
tudes 0°-25°, unbalanced in favour of the southern 
hemisphere. The Campos, Llanos, Gran Chaco areas of 
South America, parts of Central America, encircling the 
Congo basin, and many central Pacific islands (Hawaii) 
are all wet-dry tropical areas, most now developed to 

Winter, the low-sun period, is the dry time, when 

clear skies and intense sunlight take day temperatures 
to 38°C (100°F) or more. Humidity is low, and strong 
dessicating winds may blow. Summer, the high-sun 
period, is like the wet tropics, but episodic flooding is 
more common and natural erosion therefore greater. 
There are no frosts, and temperatures range 21-27°C 
(70-80°F) in the wet season, 32-38°C (90-100°F) in dry 
season. Rainfall is 25-152 cm (10-60 inches), decreasing 
towards desert margins. Windward inland slopes and 
coastal mountains may receive excessive rain to 1016 
cm (400 inches), but rain is erratic and least predictable 
towards the desert margins. Rain shadows evolve on 
leeslopes or in the lee of mountains. 

The landscape is of intermittent streams, some wadis 
and flood plains, karst (limestone) areas with sinkholes, 
cenotes, and absence of surface water (Yucatan, 
Mexico). Hills are rounded, but gully erosion can 
develop rapidly on slopes. Extensive inland swamps 
may develop in flooded areas, and lakes in rifts are 
common (Africa). Rivers often have dangerous bar- 
ways of silt and sand due to active erosion sequences. 

These regions contain the vast savannah grasslands 
of the tropics, with thorn-bush and flat-topped Acacia 
trees (Africa), evolving to steppe grassland on plateaus, 
with baobabs and dry-deciduous trees. Grasses reach 
1-6 m (4-20 feet) in the wet season, and are often burnt 
off. African areas contain enormous numbers of herd 
species: zebra, gnu, antelope, and therefore large 
carnivores. Arboreal species occur only within tree 
islands and the gallery forests of valleys. There are 
termites, ostrich, rhea, locust, and large numbers of 
reptile species and insects. 

Soils are generally more fertile and alkaline than the 
wet tropics, especially where they are less leached by 
rain towards the deserts. Cultivated land is still at risk 
from erratic rain and erosion, leaching, and wind 
effects. Due to overgrazing and fire, erosion may extend 
the desert into these areas, or into dry-summer 
subtropics. Serious soil erosion results from short-term 
shifting cultivation (less than 15 years fallow period). 

Staples are corn, millet, wheat, beans, potatoes, 
cucurbits, peanuts, cattle and goats, sheep, and game 
products. Herding of low-yield large herds is a major 
erosion hazard. Plantation crops are sugar, cotton, 
peanuts, pineapple, sisal. Exports are cattle and sheep 
products, and hardwoods from gallery forests. 

Houses and granaries are generally mud or pise with 


Design essentials are for: 

• Small domestic water storage and reticulation. 

• Hedgerow against winds. 

• In-crop tree legumes such as Acacia albida. 

• Improved stock varieties and stock management. 

• Natural herding system of local herd species. 

• Mulch use of grasses. 

• Increased tree crop of high forage value. 

• Decreased fire frequency. 

• Tree stands for fuel and structural timber. 

• No-tillage (cut and mulch) grain techniques. 

• Low bunds for water retention. 


• Chisel plow and sod-seeding techniques. 

• Greater reliance on in-village tree crop near wells 
and ponds. 

• Reclamation of eroded lands using pioneer species. 

• Keyline techniques of flood control. 

• Soakage pits and impoundment of run-off by low 
bunds or swales across slopes. 

• Tree forage and tall grass hand-fed to domestic 

• The use of manures in gardens. 

• The development of domestic fuelwood systems 
near villages. 


These are really a sub-type of wet-dry tropics, but in¬ 
fluenced by nearby continental land masses and 
oceanic winds onshore. They are confined to the Indo- 
Thailand region, northern Australia, East Java, Timor, 
southern New Guinea, and extend Latitude 0° to 35° 
north in India. Despite only about 8-10% of the world s 
land surface, monsoon areas contain large human 

Late summer heating of the continents causes 
onshore sea winds and (with luck) heavy rains. The dry 
(winter) season reverses winds from cool interiors to 
coasts, giving a cool period not experienced in the wet- 
dry tropics (temperatures: 13-21 °C—55°-70°F). Tem¬ 
peratures rise, and dry hot winds develop (to over 
38°C—100°F) in spring, with heat increasing until the 
onset of the monsoon . About 60% of the rain falls in 
summer, but rain is erratic and varies from 102-1016 cm 
(40-400 inches), depending on topography and distance 
from the coast. Floods and droughts are equally 
unpredictable, but common. Most activities are 
determined by the monsoon rain (transport, fishing, 

Tropical forests once clothed the hill slopes and river 
plains, and grasslands extended towards deserts as 
savannah. Population pressure, deforestation, and 
marginal agriculture has devastated this ecology in 
India. Dry-deciduous broadleaves are common, teak 
and bamboo once extensive. Tree canopy is less dense 
than in wet tropics, so that dense understory is also 
developed. Mangroves occupy river mouths and low 
coasts. Large native animals are now rare in the Indian 
sub-continent, but reptile life is abundant, as are feral 
or native deer, buffalo, and primates. Monsoon Ausralia 
is better vegetated, with scattered eucalypt and Acacia 
trees, riverine forests, and very low human populations 
to date. Large marsupials, feral buffalo, and marsh 
waterfowl are abundant. 

Soils are lateritic, often very hard in the dry season, 
and of low nutrient status. Some are cracking clays. 
Housing is often mud-pole structures, thatched, 
steep-roofed, with wide eaves and good drainage for 
wet period. 

Design essentials are similar to those of the wet-dry 



Special problems arise with tropical soils, in that except 
in areas of recent vulcanism such as Indonesia, soils are 
old (not renewed by glaciation) and deeply leached. 
Most of the silica and calcium is in low supply. In clays, 
aluminium ions substitute for some silica ions, giving 
soil particles a net negative charge. Especially in the 
oxidic kaolinitic soils (common in weathered volcanics) 
only kaolin clays and oxides of iron-aluminium remain. 
In these soils, the charge or cation exchange capacity 
(CEO of the soils is affected by pH- Once cleared, the 
humic particles leach out to about 30% of prior levels, 
and infertility appears in such crops as banana and 
sugar cane. There are a few ways to restore the soil’s 
ability to hold nutrients (Wayne Ralph, "Managing 
Some Tropical Soils" in Rural Research No. 117, pp. 

• Restore humus with green crop, and especially 
perennials such as Leucaena and tree legumes generally 
Any cultivation loses humus as carbon dioxide, so try 
to grow plants w'ith intercrop. 

• Now, add small quantities of superphosphate at 
frequent intervals so that plants can take it up before 
leaching. If possible, add fine crushed basalt, a scatter 
of cement powder, and use shredded bamboo or cane 
mulches for silica and calcium. Increase pH with lime 
after trees and green crop are growing well. 

• Whatever is added or available as fertiliser, give as 
a light spread all year at 6-urek intervals, until plants are 
well grown. If at all possible, substitute perennial for 
annual crop, and never practice frequent cultivation. 

Basalt, cement powder, coral, and bamboo mulch 
supply essential nutrients and increase soil pH, hence 
increase the negative charge on soil particles and their 
ability to hold calcium, sodium, phosphates against 


On coral cays, the calcium-rich sands bind to 
phosphate to form insoluble calcium tri-phosphate, so 
that a sort of cement (platin or calcrete) forms. This may 
be naturally evolved from the guano of seabirds, but 
superphosphate rapidly forms the platin by its greater 
solubility. In calcium rich tropical soils, fine rock 
phosphate yields more slowly and is therefore more 
likely to provide long-term benefits. A return of crop 
wastes as mulch is also essential, which can reduce pH 
in coral sands (pH 8-9) to a level nearer to pi 1 6.5 or 7, 
which is suitable for gardens. 

In fresh volcanic areas, or areas with volcanic dust 
deposits, soils are sufficiently rich to sustain intensive 
agriculture without such aids, but constant cropping 
will exhaust even these soils. 

There are many excellent tropical soils such as the 
alkaline volcanic soils of Indonesia, which support rich 
terrace and palm polyculture systems, and many 
tropical high-island soils where dolomite tops, or forms 
a mosaic with, recent volcanics. Apart from testing for 
minor elements, the addition a of mulch-manure mix 
creates excellent gardens on such soils, and plants show 
only minor nitrogen deficiences. These deficiencies can 
be eliminated by legume intercrop and manures. 

In the long term we must rely on tree and ground 
legumes to keep up soil health in the tropics. 
Destructive approaches (now' very well demonstrated) 
combine forest clearing, bare-soil cropping, and 
careless water run-off management to make desolate 
baked clays, brick-like and hostile, out of once-rich 
tropical forests. We have (as yet) no categories of 
"crimes against nature", but these will prove, in the 
future, to be some of the worst. 

a peculiar problem arises in that open, coarse, granitic 
sands, often very deep, will not retain mulch beyond 
one growing season. There are two approaches to these 
free-draining and low-nutrient soils: 


Palms, Albizzia spp., Inga spp.. Acacia spp., a general 
planting of adapted leguminous trees, and other native 
vegetation will establish a light canopy of leaves if 
small amounts of nutrient are added at regular 
intervals. Palms planted in mulch-filled pits will then 
establish a high crown cover, and the detritus from 
legumes can be used to establish more valuable fruit 
trees, always retaining a complete root ueb of legumes. 
Palm trunks are ideal trellis for vanilla and passionfruit 
crop. Niches and clefts in the granite mass itself will 
hold pockets of soil and mulch for valuable trees, and 
vines will establish there to cover the granite slabs, 
which maintain heat and ripen crop effectively. 

It is the mycelial web of the pioneer legume roots 
which enables us to maintain the benefit of applied 
nutrients, to reduce water use, and to establish fruiting 
trees (mango, cashew, pomegranate, persimmon, citrus, 
tamarind, lychee, custard apple, avocado) in such 
sparse and drought-prone soils. Drainage is, of course, 
excellent, and deep-rooting trees thrive. Palms suited to 
these sites are date, coconut, doum, and Borassus palms. 


It is effective to excavate long trenches in the loose sand 
(1-2 m wide, 1-1.5 m deep), to lay in a sheet-plastic 
base (upturned at one end only) or to line the trench 
thickly with cardboard, paper, carpet, and leaf and then 
to backfill with sandy loam. The deep sealed layer 
holds water and leached mulch, and household waste 

Figure 10.3 



In soils over rotted granites, such as are found on the 
high islands of the Indian Ocean, the Deccan in India, 
and where granites are left as inselbergs (domed hills). 

water can be led into these trenches to provide root 
water and nutrients. 

Otherwise, we can build log-boxes above ground 
level, carpet the box base with plastic or thick paper. 


and fill with humus-sand mixes for green crop and 
vegetables, top-mulching as needed. Large domestic 
water tanks, gleyed ponds, solid granite dams, and 
underground plastic-lined cisterns back-filled with 
sand will hold water. 

Termites, ants, and some worms are the obvious soil 
mesofauna of many arid and humid subtropical areas. 
Both ants and termites are very active in the transport 
of rotted rock and subsoil to the surface, in opening up 
galleries for the infiltration of water, and in the 
breakdown of woody and leafy plant material. Some 
species create large mounds, others build underground 
compost heaps for fungal culture, and all are active 
burrowcrs and builders. 

Termites may have a decisive role in the dynamic and 
delicate balance between the erosion of surface soil and 
the replacement of the soil by subsoil and rotted rock 
particles. They certainly have an important role in plant 
succession and distribution in savannah areas, or where 
termite and ant mounds are the only well-drained or 
elevated sites in a landscape subject to floods, or where 
impermeable clays underlie thin peats (usually with 
acid anaerobic soils). In these situations the spoil heaps 
present an ideal site for pioneer vegetation or adapted 
crop planting. 

Harris (1971) records that both the leaf-cutter ant in 
South America and termite mounds in Uganda assist 
forest spread or establish islands of taller vegetation in 
grasslands on their mounds or colonies. I have also 
observed this in the granite country in Hyderabad, 
India, and on acid peatlands in Tasmania. Such mounds 
protect soils from fire, waterlogging, and poor aeration. 
In humid areas, some such sequence as tall grasses 
( Pennisetum , Eragroslis) are followed by shrubs such as 
castor oil bean, Proscpis, and thorny legumes. Finally, an 
understory and forest may develop from larger trees 
such as tamarind, Vitex, Sapium, or palms dominant. 

Thus, we can start this process or a modest version of 
it by seeding into termite or ant mounds using similar 
species; even low ant-heaps may present a site for 
ground cover pioneers in grasslands. Harris records 
crops such as sisal, cotton, and tobacco deliberately 

cultivated on large mounds in grasslands. Palms and 
coffee can have much of their outer bark removed by 
termites without suffering loss of production. Termites 
may greatly assist the primary breakdown of logs, 
coarse stems, and hard leaf material used as mulch in 
plantations of coffee, tea, or bananas. 

It is a matter of specifying (by observation and local 
report) which useful crops or trees are left alone on 
mounds, which are attacked but remain productive, 
and which actually benefit by association with a local 
termite or ant species. Planting in ant or termite 
mounds is a particular example of niche gardening 
widely applicable to the tropics. I have successfully 
germinated daikon radish in ant heaps in grasslands as 
part of a changeover to crop production. 

Ant and termite mounds present a rich deposit of cal¬ 
cium and potash, better aeration of soil, and a faster 
infiltration of water to release minerals from such rocks 
as granites, which noticeably rot or erode faster when 
buried in a free-infiltration soil environment. 

As humus in the soil provides a good CEC, we must 
look to the provision of such humus as a priority. Some 
sources are: 

• Logs and branches of trees. These arc sometimes 
rotted in wet terraces or piled up as rough mulch 
around new tree plantings. Palm wastes are often 

• Detritus from stands of bamboo, pines, Casuarinas. 

• Aquatic weed mats and emergent water weeds. 

• Crop wastes and manures, household wastes. 

• Hedgerow, forage, and specially-grown mulch 

• Green mulch and ground cover 

U>&§ a nd. n<;hfi&.tRpugh, Mukh) 

The rapid breakdown of wood under the combined in¬ 
fluence of rain, heat, termites and fungi means that we 
can lever whole logs together, or in line cross-slope to 
act as planting sites. This technique is most useful on 
bare day soils, eroded areas, and isolated atolls (using 
the trunks of old palm trees). 

In Hawaii, a traditional strategy is to rot the logs of 


.■"• ■ ~ T 7 y r n :;- 

TW1<X PAPER. Wef) 

FIGURE 10.4 


Greywater seepage pipes along plastic-lined trenches irrigate raised, 
mulched gardens in coarse granitic sands. ‘ 


the kukui tree (Aleurites moluccensis ) in the shallow 
water of taro terraces. As logs rot. an edible fungi 
appears which is taken off as crop. The remaining log is 
then crushed and spread in the taro terrace. Leaves and 
branches of kukui and other forest trees were gathered 
tor the same purpose (terrace mulch). 

Marjorie Spears, in Queensland, Australia, has 
successfully built temporary roughwood terraces across 
a deforested slope using rejected logs, and created a 
complex and rich garden based on this strategy and 
green legume mulch. Logs are available from palms, 
although fast-growing acacia species can be previously 
close-planted for this purpose (Figure 10.5). 


Several plant species (most palms, bamboo thickets. 
Casuarma, and many Acacia species) provide silica-rich 
mulch, as do grain and nut husks and residues from 
copra operations. This can be applied as shredded or 
chopped mulch to crop or to the base of newly-planted 
trees. The silica is released for growth, and has the 
secondary effect, in alkaline island soils, of reducing pH 
(from 8.:> to 6.5 in my trials on coral islands). 

Of particular value are the fronds and spathes of 
palms, shredded or whole, and the stems and spathes 
of bamboo. Both have essential structural uses, and 
larger stands can be used to produce mulch. 

Ag natic Weeds 

Floating aquatics, including the water-fern Azalia 
(several species), the water-lettuce ( Pistia ), water 
hyacinth (Eichorma). and algal mats or fern fronds, plus 
reeds and rushes gathered from ditches, are excellent 
crop mulch. Azalia has largely replaced kukui (Aleurites) 
as a taro mulch in Hawaii. Pistia has been successfully 
used >n Africa, and water hyacinth in many areas. 

Azalia and algae such as Artabaena (one species of 
which nests" in the glutinous sacs in Azalia) provide 
nitrogen. In the dry-wet tropics, shallow flood-water 
bunds collect or produce these plants, which can be 
gathered as rolls of dry material when the water dries 
out in the winter period, thus providing garden mulch 
in abundance from temporarily impounded water. John 
Selman of Cooktown (Australia) has used algal rolls in 
this way for his garden plants. 

Crop Wastes and Manure 

The husks of corn, kitchen wastes (including bones), 
and human and animal manures are invaluable tropical 
garden mulches and nutrients, and most need only 
burial near tree roots or in growing mounds for safe 
disposal. Cardboard and newspaper, where available, 
are valuable grass-suppressing weed mulches, and a 
cover of nut husks completes the job. In the Seychelles 
cinnamon leaves and branches from pollarded'stumps 
are considered an excellent mulch for vegetable crop' 
and the bark is a valuable spice. 

Hgdgero w and Mulch Plants 

All hedgerow ( Hibiscus , Casuarina, banna grass, palms 
leguminous trees such as Gliricidia. Acacia and Prosopis) 
are almost continual mulch sources. The legumes 
provide in-crop shelter (see later section on avenue 
cropping). Lower garden windbreak, especially 
Iemongrass (Cymbopogon citratus) and comfrey 
(Symphytum officinale) are as useful in preventing 
kikuvu grass intrusion as they are for repetitive cutting 
tor mulch in the vegetable garden. Many people now 
use both these species as a combined kikuvu barrier 
and mulch crop (Figure 10.6) 


In and around gardens and trees, soft herbaceous plants 
such as nasturtium, comfrey, marigolds, tobacco plants, 
and the tops of mature taro plants and other Araceae not 
only suppress grass, but provide a constant source of 
"slash" mulch. Even more valuable are such soft 
legumes as Sesbania, vetch, Haifa clover, cowpea, lablab 
bean, soya bean, Desmodium. Suratro, and Centrosema. 
These can be slashed or (in wet-dry tropics) 
interplanted with grains to give a nitrogenous ground 
cover, aiding in the suppression of grasses. Lablab dies 
down just before grains ripen in the winter dry season. 

Thus, a combination of growing and gathering mulch 
enables us to create a rich humus for gardens over clays 
or sands, in loose volanic cinder, on a ‘a lava, and in 
loose coral atoll sands. Each of these situations can 
successfully produce mulch. 

Some difficult mulch such as hibiscus. Lantana, and 
weeds which tend to resprout from cuttings or seed if 
mulched (several grasses and hedge species) can be 
routed to gardens via poultry or cattle pens (where 
seeds are removed and foliage eaten). They can also be 
shredded for anaerobic digestion in biogas plants, 
bagged in large plastic bales exposed to the sun (where 
they "cook” to a weed-free silage), or simply bundled 
and immersed to rot in covered water pits. In fact, some 
such re-routing is ideal for the primary processing of 
plant wastes that promise to infest gardens if un¬ 
treated. Pigs eliminate or eat the nut-grasses, rhizomes, 
bulbs, and sedges that resprout from compost. 

All else failing, even a plastic sheet mulch has ex¬ 
cellent effects on row crop, preventing rain splash and 
nutrient leaching, and at the same time condensing 
groundwater at night. It does not, however, add to the 
humus content of soils, nor to the cation capacity of soil 
structure, and may even release unwanted chemicals to 
the soil. 

The value of surface mulch in weed suppression is a 
major factor in lowering garden work. For this reason, 
any mulch should be thickly applied 20-25 cm (8-20 

TABLE 10.1 

MULCHES Maize Cowpea Soyabean Cassava 

Rice husks 











Elephant grass 





Millet straw 





Legume wastes 










Bare ground 





•Heavy yields are emphasized. 

(After B. N. Okigboand R. Lai. Residue mulches and 
agriculture .) 

inches) deep when first establishing home gardens. 
Later mulch can be derived from green herbage and 
borders or windbreaks. 

B. N. Okigbo and R. Lai in Residue Mulches and 
Agrisilviculture (International Conference on Ecological 
Agriculture, Montreal, 1978), in mapping strategies to 
cope with increasing land pressures, found that 
no-tillage systems maintained or gained yields for 
maize in Nigeria, and increased yields from mulched 
crop for cowpea, soya bean and cassava. 

I have selected out some natural mulches from the 
more extensive original table given. Mulch trials are 
compared with bare ground (on the last line of Table 
10 . 1 ) 

Maize had a marked positive response to legume 
straws or watcrplant (Pistia) mulch, while the legumes 
themselves responded well to grass and sawdust 
mulch, and cassava to both legume and grain husk 

FIGURE 10.6 

Grasses are kept at Day by barrier plantings; mulched grasses can be 
planted out that day it paper or cardboard is used over undug grasses. 

Although plastic mulch has a good effect on all crops, 
it does not add humus to soils, and is therefore not as 
appropriate to a remote village situation where soils 
must be built up from wastes and from mulch. 

However, every type of organic mulch increases 
yields, and we should therefore use all available 
materials for soil restitution. Mulch provision is the 
cornerstone of tropical home gardens, and green mulch 
and tree legumes the essential accompaniment of main 
crops and tree crops. 

Special mulches may be used in tropical areas, grown 
to provide N, P, K (legumes, comfrey, Pultanea), and to 
increase or decrease pH. Pine and legume mulch may 
benefit the growth of bromeliads (pH 4-5), buckwheat 
and nut husks serve to raise the pH of garden soils, as 
do many bark mulches. 

For fire control, too, it pays to rake under bamboo 
and clump canes, and re-route the leaf mulch through 
animal bedding or poultry strawyards. Branches of 
legumes and forage trees may also be used in the same 
way, on their path to the garden. 

In the rampant grasslands that replace fallen forests, 
there is little else we can do than to strip-mow and 
mulch while trees re-establish. The timing of slashing is 
important, as seed-free mulch (called second-cut grass) 
is best for placing around valuable crop. Seed-head 
mulch should not be placed in gardens or areas where it 
might be a nuisance. All species of weeds and grasses 
give weed-free mulch when not in seed. Many useful 
tree species provide leaf mulch, and so are excellent 
also for interplanting with crop, for example tamarisk 
in dry areas, Casuarinas in sand, and legumes in all 

There is absolutely no excuse for burning any organic 
wastes in the tropics, as even large logs quickly rot 
under the onslaught of fungi, termites and beetle 
larvae. At the same time, logs provide cross-slope 
barriers against monsoon erosion, until new trees take 

Coconut husks have a variety of uses, not the least of 
which is as mulch for a valued crop such as vanilla 
orchids. Their one drawback is that they hold small 
sections of water which will breed mosquitoes, but on 
many islands they will also be available (with palm 
fronds) to shred to a first-class mulch of high potash 
value, to bum and steam to activated (filter) charcoal, 
or to be used as a solid fuel. Shredded bark and broken 
shells are ideal mulches for ginger, tumeric, and vines. 

1 have not found any crop or tree suited to the 
specific locality that does not grow, produce, and thrive 
in mulch, nor any widespread pest that grossly affects a 
total polyculture yield. Ginger, taro, beans, bananas, 
palms, fruit trees, flowers, yams, sweet potato, melons, 
etc etc. have been trialed in thick mulches of straw, 
fronds, nut husks, cardboard, and sawdust. A thick 
mulch almost totally eradicates kikuyu grass and other 
persistent grasses. In the field situation, extensive 
mulching is often impractical, particularly if it is carted 
in from off the site. However, a pioneer crop of 
quick-growing tree Acacias, bananas, legumes such as 
lablab, deep-rooting comfrey, and a grove of bamboo 
and palms will provide continuous mulch for gardens 
and main crops, fruit trees and valued plants. 

Growing in exhausted or poor tropical soils is 
possible, but the early work of rehabilitation takes hard 
work, seed, essential fertiliser resources, and a strategy 


of starting small and expanding the system at the 
periphery. Dense planting of nucleus areas plus mulch 
is the key strategy. 

_ 10A _ 


On level ground or gentle slopes (2-8°) in the wet-dry 
tropics, a series of large contour banks or swales have 
an excellent soil preservation effect. Coupled with the 
gradual development of a terrace, the retention of 
wet-season water, and mulch-providing hedgerow, this 
ensures a stable situation. Between the main hedges, 
mulch hedgerow and borders can be developed in crop, 
or the terraces can be flooded seasonally for irrigated 
crops (Figure 10.8). 

On very flat sites (less than 4°), a series of raised 
mounds or ridges can operate to drain crops in very 
wet areas, or to impound water for absorption in drier 
areas. Pits can also be used only where rainfall is less 
than 76 cm (30 inches), or where soil drainage is good. 
Thus, cassava, yam, and cucurbits are mounded in 

areas where drainage is a problem and rainfall intense, 
and pitted in dry areas or savannah-dry seasons. Pits 
retain mulch and moisture, as they do in desert areas. 

Almost every slope benefits from earth-shaping for 
soil conservation. Hand-made slope terraces need to be 
narrower (to 3.5-6.5 m—12-15 feet) than machine- 
made systems. 

Garden terraces on ocry steep humid slopes must be 
kept narrow, and in sets of 6-8 downslope, otherwise 
instability may result. Borders can be kept vegetated 
with trees (Figure 10.11). 

Classical wet rice and taro terrace has water 
continuously led into the top terrace of the series, and 
each has a drain and sump to regulate water level. Fish 

FIGURE 10.9 


Mounds increase yields ot yams; ridges of cassava and sweet potato; 
pits for taro, arrowroot, and mulch grasses. Terraces need such 
detailed earthworks. 


may be grown in the deeps of such terraces (Figure 
10 . 12 ). 

in stable clay or clay-loam soils, terraces not only 
hold and infiltrate water, but permit mulch application 
with minimal leaching losses. Where no streams exist to 
feed the terrace system, DRY TERRACF. holds the soil 
against erosion in cropped areas. Lacking streams, a 
deep mulch keeps terrace soils moist. Where a stream, 
or part of a stream, can be led to upper terraces, wet 
crop such as rice, taro, watercress, kangkong, and water 
chestnuts (Indian or Chinese) can be cultivated in 
water-level controlled padi. This is the rich WET 
TERRACE culture of Asia and Oceania. 

Essentials are: about one-half to one-third of the total 
terraced area should be devoted to mulch tree crop 
providing fodder for livestock or direct leaf and branch 
mulch to terraces. Ideally, the upper one-third of hills, 
the very steep slopes of 30° or greater, terrace 
side-borders, and the outer faces and crowns of bunds 
(walls) should be planted to productive and mulch- 
paxlucing tree and ground crop. This not only adds to 
the terrace stability—many of which have existed in 
production for up to 5000 years, e.g. the wet terrace cul¬ 
tures of the Ifugao people of the Philippines—but will 
also provide a local manurial-mulch crop for terrace 
cultures. Included in such mulches are the crop wastes 
of the proceeding crop. 

SpcKi fje Q.ipwin& gituations on Terraced Lands 

• Banks and bunds: the rim of the terraces, and 
stepped bunds made for tree crop. 

• Slope faces and walls. 

• On trellis out from bunds. 

• In and around ditches and drains. 

• On steep (unterraced) slopes. 

• The flat area of the terrace itself. 

Dry Terrace Crop Species 

• Millet: summer or dry periods. 

• Dryland rice: spring-summer. 

• Barley, wheat, rye: winter and cool periods, spring 
wheat varieties, Brassicas, fava beans. 

• Amaranth: summer grains, spring greens. 

• Quinoa: summer grains. 

• Rape/mustard: winter oils and oil seed. 

• Lentils, peas: intercrop and nitrogen fixing grain 

• Grams and pulses: intercrop and nitrogen fixing. 

• Tagasaste, banna grass, comfrey, Leucaena, crop 
wastes and straw. 

ga.rdgn_Tgri^ ^ N. gar Hpmg ? 

Banana, papaya, melons, chilies, peppers, cucur- 

FIGURE 10.11 


A senes should be limited to 6-8 at one place, forested above and 
below, and to the sides, for stability, paths slope alternately to spill 
excess run-off. and are mulched. Twice annualy path mulch is lifted to 
uphill terrace beds 

rwwc pvoyjr akp 

n\AC\iof-mse ovp+ig& x 



-rv^6£ A*e- Vi MICW^L AWD 


rbits, maize, beans, sugar cane, cultivated green-crop 
Brassica, edible Chrysanthemum , edible Hibiscus, rosella, 
horseradish tree (Morin^a). coconut, mango. 

Vino Crop Off Bund_Fa ces 

• Chavote, cucurbits, beans, passionfruit. kiwitruit. 

• Bamboo on borders provide trellis material, as do 
rot-resistant timbers. 


• Tree legumes, banna grass ( Pennisetum ), lemon- 
grass. Vetiver grass, comfrey, bamboo and palm fronds, 
Aleurites spp., Cimiamonum spp. 

Slope Stability 

. Contour strips of Vetiver grass, lemongrass. banna 
grass with tree legumes not only replace contour ridges 
but trap soil particles, and is a cheap wav to terrace , 
even on steep slopes. These strips provide mulch for 
trees and intercrop (Figure 10.13). 

F ^ntials and Va rjatignsml^g^gSy^tems 

• Borders; and uphill, steep-slope, forest crop 
planted and selected for mulch value and fodder, or 

. Animal sheds (ducks, pigeon, poultry, pigs. t*es> 
over top terraces; manure on a washdown system. 

• ln-crop mulches such as beans, Azolla, clovers. 

• Staggered, short sets of terraces for steep slopes and 
high rainfall, compared with more continuous and 
longer series for winter-dry irrigated terrace. 

. Deep areas in terraces for fish/crayfish/ shellfish 

refuges. , 

. Vines over all or part of the terrace to aid such 

crops as taro. 

• Bunds planted in clover, beans, comfrey, 
lemongrass, fruit crop. 

• Splash stones or splash plates for falling water; 
methods of draining terrace. 

• Border drains in terrace to keep soil dry tor mid¬ 

season crop. 

10.5 __ 


Optimum comfort levels for people are at dry-bulb 
temperatures of 20°C (68°F) in still air (winter), and 
25°C (77°F) in summer, subject also to individual pre¬ 
ferences. Above relative humidity levels of 40%, we 
effectively add 1 °C to dry-bulb temperature for every 
4 % increase in humidity. As average summer humidity 
in wet-dry tropics commonly exceeds 50%, and long 
periods of'humidity of 70% or so are experienced, there 
are times when sensible temperature exceeds 30°C 
(86°F), and heat stress results. 

In homes, a useful indicator is a wet-bulb thermo¬ 
meter, where the mercury bulb is kept damped by a 
cotton wick drawing from a beaker of water. Below 
18°C (65°F) wet-bulb temperature, we can remain fairly 

Factors that accentuate heat are nearby radiant 
surfaces and lack of air movement. For a nearby radiant 
heat source (wall or pavement) that exceeds 38 C 
(100°F), we can add 1°C (per degree radiated) to the air 
temperature, and conversely, we can subtract 1C for 
any air flow above 1 m/second. 

Evaporative cooling in dry air greatly reduces heat, 
but as the high humidity periods of tropics do not 
enable us to cool by sweating, we must therefore use 
every strategy available to de-humidify air (mainly by 
cooling), to cast shade, to develop cool surfaces, and 
above all to induce cool air currents in houses. Over¬ 
shading trees, attached shadehouse, white extenor and 
interior surfaces, and clear-path breezeways are 
essential design strategies both in equatorial and 
sub-tropical climates. 

In many continental subtropical locations, we are 
faced with dual problems of quite intense winter cold, 
with some frosts (and rare snows), and very humid and 
hot summers. Thus, the sort of house we need to build 
has several unusual characteristics, and needs perhaps 
more careful planning than either equatorial houses 
(where reducing heat is the only problem) or temperate 
and boreal housing (where providing heat is the only 




L t^rlOK) 

A 5y^reM wmcw r£<x>v(e$ 
I^TlMg^TMe S?R£>/*M 

4 cf -me cvuiva - 


'* 6X (NCReA&t /M TcyAc 
epfici6Ncy pot? sEMi-Aeif* 


M 5eM' ^« L e5 ,l " 

op. A^> 

FIGURE 10.13 

provide cheap erosion control on contour or Bund stabilisation; both 
these grasses dump readily, have tew seeds, provide mulch, and hole 
soil movement. 


The subtropical house needs to both heat and cool. 
For heating, it needs to have an insulated slab floor or 
trombe wall, and for the cooling system it needs 
induced or forced cross-ventilation from a cool or 
shaded area to an updraught area. 

The secondary effects of high humidity range from 
the merely annoying (salt will not pour) to far more 
serious effects (clothes, food, film, and books mildew). 
Thus, we face two sorts of problems in house con¬ 

• Human comfort. 

• Safe storages; for these we need both cool and 
warm storages, but both need to be dry. 

Human comfort is greatly aided by these factors: 

• SHADE: Light and heat are both excluded as 

incoming radiation in shade. Shade is particularly 
critical on massive walls or over water tanks close to 

• TRANSPIRATION: Plants can assist cooling by 
transpiring. Partial shade helps this factor in understory 
species except in extremely wet conditions. 

• COOL BODIES: Urge heat resevoirs used as water 
tanks and relatively cool blocks of (shaded) stone, 
concrete, and mud brick absorb heat from the air and 
from warm bodies. Conversely, hot radiant bodies 
adversely affect us. 

• AIR FLOWS: Even low air flows from shaded areas 
greatly aid both transpiration and evaporative cooling. 
To create such air flows we need to develop both 
relatively hotter and colder air sources and to provide a 

'Mar 1 .v/'f, 


PKAW vVTfc* fo 


FIGURE 10.15 


The sloping side-bank here is shown planted to ideal mulch trees, cut 
or coppiced to enrich terrace crop production Oram pipes are 
adiustahle to dry out terraces 


cross-flow airway. Even a fan, simply stirring the air, 
aids in human comfort. 

cook-stoves and hot-water systems are best placed in a 

semi-detached kitchen in the tropics. Commonly, these 
are reached via a vine-covered shade area, are 
themselves shaded by palms or trees, and have wide 
eaves and ceiling vents for hot air escape. 


Heat can be used via metal roof areas, hot-water 
storages, and attached glass-houses or solar chimneys 
to vent hot air and create updraught, which in turn 
provides a heat engine to draw in cool air. The 
essentials of good cross-ventilation are that the flowing 
air has a simple pathway to follow (no unnecessary 
comers to turn), and that large vents are used to allow a 
good volume of air through workrooms and storage 
areas (Figure 10.16). 

Probably the best cooling systems in tropical houses 
are those which use a hot roof or metal chimney to 
draw in cold air from earth-cooled underground 
tunnels or pipes. As this cool air is dense, it will 
naturally flow downhill or sink to lower levels; this cool 
air can be drawn into houses via a positive exhaust 
system, or actively fannned into rooms. 

To cool a pipe and lead off the heat continously, we 
need to construct a trench 1 m deep and 15-20 m long 
cut in the earth, drain off the condensed water (ideally 
making it self-draining to a lower slope), and provide 
this trench or pipe with a sloping floor. The intake end 
can be box-screened to keep out mice, and shaded by 
plants. Outlets can be floor grills or a louvred "cup¬ 
board" opening to the pipe or pipes in the trench 
(Figure 10.17). 

Natural cross-ventilation can occur if a well-sealed 
room has a roof vent or chimney to create an up¬ 
draught. Some forms of air scoop may help this process 

The cold tunnel solution is very effective, and can be 
used together with evaporative cooling in desert hous¬ 
ing, but it is also expensive, and difficult to fit to an 
existing house. For this reason, many homes can be suf¬ 
ficiently cooled by the use of vertical shutters acting as 
air scoops—a satisfactory solution on subtropical 

tradewind coasts. Or a shadehouse can be added to the 
poleward side of a house and cross-ventilated to a 
well-vented GREENHOUSE on the sun side of the 


Some essentials of truly tropical housing (no cold 
season) are: 

Site Choice 

• Orientation is to prevailing winds, not to the sun. 
Cooling is by cross-ventilation. 

• Shaded valley sites greatly aid cooling and shelter. 

• Induced ventilation is essential, achieved by siting 
in palm groves or overshaded by trees, which should be 
permeable to wind at ground (house) level. Palms and 
trees can be pruned up the trunk. 

• Site sheltered from hurricanes, tsunami, and 
vulcanism, sited on stable soils that resist mudflow in 
heavy rains. 

House Desig n 

• Walls white or reflective, overshaded by wide eaves 
and palms or trees. 

• Heat sources such as stoves and hot water systems 
detached from the main structure (e.g. outdoor 

• Wall-material light, even permeable to wind 
(woven matting and mosquito screens). 

• Mass, if any, internal to rooms, smooth and 
white-painted. The whole house can be of light 
construction on the outer walls. 

• Vertical louvres and window shutters aid in 


mvx., fi poufirf 

; Mixep kaTH 
i-NC€M Le*F*o*^t 






FIGURE 10.19 ^ 


Wrth its lid sealed with mud or tar. and with an air-lock for 
£X?5 i sca ^ : a nea,b V ,erm ent provides CO? which kills 

| •iTlU, THA.'j 


• In hurricane areas, a strong central core or refuge 
may be needed, or an earth-bank shelter raised to 
protect the house; cellars should be entered above 
ground due to flooding danger in hurricanes, or well 
sealed against flooding. 

• V " y s,r ° n * ^-bracing, deep ground anchors, 
and strapped timbers may be necessary if powerful 

l 10 ,he area Lar S e bamboo groves 
placed to the windward will bend to the wind without 
breaking, protecting the house. 

shl| W mT. ,ha,C /\° r ,ile ' S im P ractical ' a vented 
sheet metal roof. In this case a thin (12 mm board) 

a " d S ° ffU ,inm 8 «" be of perm- 
able netting or screened to allow an air flow to the roof 
space and thence to the exterior via high roof vents. 



THe Wet * ason i$ ,he " hun 8 r >' 8 a P"» where 
plants are growing, but too young to harvest. Early in 
his season the soil is soft enough to plant and establish 
trees, but plants must be well-timed as the drv season 
«s long-lasting. Planting too late is to risk drought 
before ripening of the crop. Vegetable crop is started at 
either end of the wet season. Water storages (Chapter 7) 
are essential, no matter how modest, for garden, tree 
crop, and diversity in yield. Moulds, mildews, and root 

fungi are encouraged by humidity, and it is best to use 
resistant plant varieties or root-stocks. 

SPECIES: Mango, papaya, sapote, banana, limes, 
coconut, cashew, macadamia nut, breadfruit, mound- 
planted avocado and pineapple, durian, and so on are 
the garden and orchard framework, as are any pro¬ 
ductive palm crops. Large legumes such as Inga. 
Glmcidia, Leucaena. Cajanus. and so on are essential 

In the vegetable garden, yam and sweet potato yield 
better than, or in place of, potato. Adapted small-fruits 
and tomatoes of wilt-resistant strains grow well 
Amaranth is a good green and grain crop. Lima, velvet, 
and Dohchos beans trellis on free legumes. Forage and 
ground legumes provide green mulch and help 
suppress grasses, as do comfrey and lemongrass. 
Vh.lies peppers, and the range of tropical vegetables 
are preferred to temperate species. 

Bamboos, balsa, teak, palms, and mahogany provide 
structural and craft materials, rattans can be 
encouraged along waterways and in mangrove edges. 
Oil palm jelly palm, Bactras, Maurantia, saiak palm and 
doum palm provide trusses of useful fruits. 

RESTS: Large insect pests (locust, cicadas, sucking 
bugs) are plentiful; guinea-fowl or chickens on range 
are some defense. Native rodents and pigs can be 
damaging, and pythons rather than foxes take poultry. 
Termites and ants largely replace worms in 
soil building, and buildings must be constructed to 
resist them. Geckoes in houses eat many insect pests, as 
do wolf spiders. 


DOMESTIC ANIMALS: Pigeons and bees are most 
easily protected from predators by elevation on pole 
structures, or over shallow ponds. Guinea fowl, franco- 
lin, pheasant, and bantams provide essential foraging 
and insect control services. The guinea-pig aids small 
tree establishment as they "chip 1 the base of young 
grasses, and small pigs of Taiwanese strains provide 
orchard-fruit garden scavenging duties. Waterfowl and 
aquatic species add yields to water storages and assist 
in grass control. 

HURRICANE DAMAGE: can be limited by raising 
large earth banks, selecting valley garden sites, 
screening plantings with bamboo groves, establishing a 
general tree canopy through garden and plantation, or a 
combination of these strategies. Oversize swales aid 
wet-season water run-off control and diversion to 


SPECIALIST CROP: There is a wide range of 
specialist crop potential, from rubber (Hevea), betel- 
nut, chalmougra oil, and chicle to essential oils and 
medicinals. Many are suited to primary processing in 
remote locations, or conversion to commercial-quality 
end-products. The high value of processed product 
enables smallholders or cooperatives to pool research 
and processing facilities, and to select high-yielding 

INTERPLANT: As well as the essential legumes, a 
scatter of Banksia , Casuarina. Gigatperma calaspora , and 
Pultenea with their mycelial associates will fix 
phosphate and return it via leaf mould. Several plants 
"pump" sugars or carbohydrates into soils, while 
leaf-sucking insects and scale insects exude sugars 

FIGURE 10.20 


Based on Japanese typhoon-proot coastal housing, bamboo groves 
provide a flexible wind barrier. Earth mounds Houses wen-braced and 

ViNe ov£«. 


FIGURE 10.21 


Based on the Fijian bur6. Earth-sheltered and well-fastened 
(traditionally by complex rope cross-binding) this house is ideal for 
hurricane areas, cool living, strength, cheapness, and uses only local 

•>ec-p<?NJ^ S’lAT'J vje«/ 
Of wAU- 

IrJ M/AU^ 

FIGURE 10.22 ^ 


Sunken between earth berms or in natural sheltered valleys; palm and 
bamboo to seaward Heavy emphasis on root crop for emergency 

food, fast regrowth. House well-braced and anchored, low profile 


from stems. Dilute molasses or cane and sorghum sugar 
juices and stems also activate soil fauna. Marigolds, 
neem tree leaves or berries, and pyrethrum daisy 
control soil pests and provide insecticides or water 
insect control. The neem tree is often planted to 
overhang ponds, so that the berries that drop control 
water-flies and mosquitos. 

Established tough grasses of the savannahs resist 
gardens, and need to be mulched or overshaded with 
tree canopies. Essentials are: 

• To mound or raise garden beds for good drainage 
in the wet season. 

• To use mulch and mulch-tree species to create 
topsoil for gardens. 

Where logs exist, they make ideal garden bed edges 
to hold mulch and soil. 

Gardens have been devised for many tropical areas, 
usually containing the following: 

• Designed for full nutrition for an average family. 

• Water conservation and safe water disposal 
(hygiene) a necessity. 

• Species chosen to suit local cultural preferences. 

• Sufficiently varied to survive reasonable climatic 
change, or seasonal irregularity. 

• Protein sources, livestock; their forages, or 
grain/legume replacements for meats. 

• Water routes and use. 

• Basic foods or staples 

• Fresh vegetable and fruit for vitamins, minerals, 
varied uses. 

• Some fuels, medicinals, flowers. 

The elements in Figure 10.23 are those that make up 
the house structure itself, and those that make up the 
garden, hedgerow, livestock and path access struc¬ 
tures. The best way to use this section is to read it 
through very carefully, study the plans and diagrams, 
and then improve it, or better it to fit to a specific site. 


Room size and number is adjusted to family size, but is 
basically a simple, easily-heated and cooled structure, 
preferably on slab or raised pise floor, and preferably 
edge-insulated. The induced cross-ventilation acts to 
cool and heat as per Figure 10.16. In addition, vertical 
sashes or shutters to each room help to scoop air in. 

In hot periods, the main living area is outside rear, or 
under a similar porch trellis to the front if the people 
prefer to be seen from the road (as is the case in most 
close-knit societies). The side trellises are seen in Figure 
10.17. Materials can be local, as can any insulation. 
Glass is needed, as are some pipes or drains of stone, 
and a tank. 


How thq Gar den .Work?..(See Figure 10.23) 

First, it accepts all water and wastes of use. Only plastic 
and glass or metal are not used, althoug